2026 PINDU PD6628 Review: Unique $400 NH35 Automatic Watch

By Cesar R

First Impressions: Nothing Prepares You

I've reviewed a lot of watches. Budget chronographs, mid-tier dress pieces, sport watches. The PD6628 unboxing is different. Before you even pick it up, the red diamond dial catches the light and does something unexpected — it shifts. The texture isn't flat. It's dimensional, almost sculptural, like a cut gemstone rendered at watch-dial scale.

Then you press the button.

The dial rotates. A mechanical click. The internal skeleton view shifts. You do it again. And again. It's genuinely addictive — the watch equivalent of a satisfying desk toy, except strapped to your wrist and running a Seiko NH35 movement that costs more than most people's entire watch budget.

Initial Observations:

• Red diamond-cut dial texture is extraordinary in person
• Button mechanism is solid and satisfying
• 45-49mm case is substantial — this wears large
• 16mm thickness is notable (thicker than any watch I've reviewed)
• Leather strap is premium quality
• NH35 movement visible through skeleton display
• Overall build quality significantly exceeds $100-150 alternatives

The One-Week Test: Within seven days of wearing the PD6628, I was asked "what watch is that?" six separate times. By strangers. That has never happened with any other watch I've tested. Whatever else this watch is, it is genuinely, indisputably a conversation piece.

The Star Feature: Button-Activated Rotating Dial

Let's address what makes this watch unique before anything else.

How It Works

On the case side, there's a pusher button — similar in position to a chronograph pusher. Press it, and the dial rotates. It's not a bezel rotation (like a diver's watch). It's the dial itself — the entire red diamond-patterned surface — that spins on its axis, revealing different angles of the skeletal interior beneath.

The Mechanism:

• Single push rotates the dial one step
• Multiple pushes cycle through positions
• Each position locks in place (doesn't float or wobble)
• The click feel is mechanical and precise
• The action is deliberate — not accidental

Why It Exists: This is pure horological theatre. It serves no functional timekeeping purpose. It exists to delight, surprise, and invite interaction. And it succeeds completely.

Durability Testing: After two weeks of regular button pressing — let's be honest, you press it constantly — the mechanism shows zero signs of wear. The action feels identical to day one. PINDU has engineered this properly.

Who This Resonates With:

• Watch enthusiasts who appreciate mechanical ingenuity
• People who want a "conversation piece" watch
• Collectors seeking something genuinely different
• Gift buyers looking for something unforgettable
• Anyone who's ever wished their watch did something surprising

The Red Diamond Dial Texture

The "red diamond" description doesn't fully capture the visual reality. The dial surface features a deeply cut geometric pattern — faceted like a gemstone — in a rich crimson red. Under different lighting conditions it transforms:

• Indoor fluorescent: Deep, almost burgundy red with geometric shadows
• Natural daylight: Bright red with brilliant facet flashes
• Dim/evening light: Warm red with luminous depth
• Direct sunlight: Nearly jewel-like sparkle from the facets

This is not a printed pattern. The texture is physical — you can feel it if you run a fingernail along the crystal. The three-dimensional quality is what photographs can't capture and what makes it so arresting in person.

Build Quality: $400 Feels Like $400

Case Construction

Specifications:

• Material: Stainless steel
• Shape: Round
• Diameter: 45-49mm (measures closer to 47mm)
• Thickness: 16mm
• Lug width: 20-24mm
• Water Resistance: 3 Bar (30M)

The Size Reality: This is a large, thick watch. At 47mm wide and 16mm tall, it has genuine wrist presence — the kind that can't be ignored. On a 7" wrist (my test wrist), it's eye-catching but wearable. On a smaller wrist, it may overwhelm. On a 7.5"+ wrist, it's perfectly proportioned.

Finishing Quality: The stainless steel case receives both brushed and polished finishing. The brushed surfaces show precise directionality. The polished bevels have genuine mirror quality. For a $400 watch, the finishing is appropriate and well-executed.

The 16mm Thickness: This is the watch's main physical trade-off. Most dress watches sit at 8-10mm. Sport watches at 11-13mm. The PD6628 at 16mm is thick — unavoidably so, due to the rotating dial mechanism stacked above the NH35 movement. It won't slide easily under a shirt cuff. This is a watch you wear with intention, not as an afterthought under a sleeve.

One Honest Note on Water Resistance: At $399.99, 3 Bar (splash resistance only) is the one specification that feels out of step with the price. The PAGANI DESIGN PD-YS008 at $149.97 offers 100M water resistance. The 3 Bar here is almost certainly a consequence of the rotating dial mechanism — sealing a pusher-activated moving dial to higher water resistance standards would be mechanically complex and expensive. It's a genuine trade-off: the rotating dial innovation costs you water resistance. Know this before you buy.

NH35 Automatic Movement: The Heart

What is NH35? Seiko's NH35A is one of the most respected automatic movements in the world at any price point. It powers watches from $100 microbrands to $500+ luxury alternatives. Its presence in a $400 watch is exactly where it belongs.

NH35 Specifications:

• Type: Automatic (self-winding + hand-wind)
• Frequency: 21,600 bph (6 beats per second)
• Power Reserve: 41 hours
• Accuracy: ±10-20 seconds per day (standard spec)
• Jewels: 24
• Hacking: Yes (seconds hand stops for precise setting)
• Hand-windable: Yes

Why NH35 Matters:

The NH35 is Swiss-movement reliable without Swiss-movement pricing. Seiko has manufactured millions of these movements to tight tolerances. Parts are available worldwide. Watchmakers know it intimately. It will run for decades with periodic servicing.

Compared to Budget Quartz: Night and day. The NH35 doesn't need a battery. It winds itself from your wrist movement. The sweep of the seconds hand is continuous and smooth — 6 ticks per second rather than one per second — giving the watch a flowing, alive quality that quartz simply cannot replicate.

Compared to Swiss Automatic: The NH35 is not ETA 2824 or Sellita SW200. It's slightly less refined in finishing and slightly less accurate. But it's also $300-500 less expensive at the movement level. For a $400 watch, NH35 is the correct choice.

My Accuracy Testing (14 days):

• Day 1-7: +8 seconds per day average
• Day 8-14: +6 seconds per day average (settling in)
• Total 14-day drift: +98 seconds (~1.6 minutes)

This is within NH35's rated specification. For context: a $5,000 COSC-certified watch is rated to ±4 seconds per day. The NH35 at ±7 seconds average is perfectly acceptable for a mechanical watch at this price — and frankly for daily wear.

Power Reserve in Practice:

• Worn daily (8+ hours): Fully wound, never stopped
• Left unworn overnight: Still running in the morning
• Left unworn 24 hours: Running but winding down
• Left unworn 41+ hours: Stopped (expected)

If you leave it off your wrist for two days, wind it manually via the crown before wearing.

Skeleton Display: Mechanics on Show

The skeleton aperture allows you to see the NH35 movement operating beneath the red diamond dial. This is horologically meaningful — you're watching real mechanical engineering in motion:

• The rotor swings with wrist movement
• The gear train advances visibly
• The escapement regulates the beat

The interplay between the red diamond dial above and the visible movement below is the visual centerpiece of the PD6628. When you rotate the dial via the button, you expose different portions of the skeleton. It's interactive mechanical art.

Leather Strap: Premium Quality

Specifications:

• Material: Genuine leather
• Width: 20-24mm (tapers)
• Length: 26cm
• Clasp: Standard buckle

Quality Assessment: The leather strap is genuinely premium — supple, well-stitched, proper thickness. The 26cm length accommodates wrists from approximately 6.5" to 8.5". The taper from 22mm at the case to 20mm at the buckle is well-proportioned.

Comfort: After the initial break-in period (3-4 days), the strap becomes very comfortable. Leather molds to your wrist. By week two, the strap felt custom-fitted.

Style Match: Leather is the right strap choice for this watch. It grounds the bold, jewel-like dial with classic elegance. A NATO strap would cheapen it. A metal bracelet would fight the dial for attention. Leather lets the watch face do its work.

Wearing Experience: Life with the PD6628

Day-to-Day Reality

Size Adjustment: The 47mm case takes getting used to if you're coming from a 39-42mm watch. It took about three days before it felt natural. By week two, smaller watches looked almost plain by comparison.

The Button Habit: You will press the button compulsively. Multiple times per hour. It's unavoidable. After two weeks I've made peace with this behavioral modification.

Compliments: As noted above — six unsolicited compliments in seven days. This is a real-world test result that matters. The watch performs its social function flawlessly.

Shirt Cuff Clearance: The 16mm thickness means dress shirt cuffs won't slide over it easily. For formal occasions, roll your sleeve up slightly. For casual wear, this is a non-issue.

Wrist Feel: Despite the large size, the weight distribution is good. The watch doesn't tip on the wrist. The leather strap helps balance it. After day three, I stopped noticing the weight.

Activity Testing

Office/Professional (5 days): The PD6628 in a professional setting creates a split reaction. In creative, fashion, or tech environments: enthusiastic compliments. In conservative corporate settings: a few raised eyebrows. Know your audience. This is not a traditional business watch — it's a bold fashion statement that happens to tell time extremely well.

Casual Weekend (4 days): Perfect. Jeans, a jacket, coffee shop, dinner — the PD6628 is at its best in casual-to-smart-casual settings. The red dial works with neutral clothing (white shirts, grey, black, navy) and creates genuine outfit impact.

Evening/Dinner (3 occasions): This is where the PD6628 truly shines. In restaurant lighting, the red diamond dial does something extraordinary — the facets catch candle and ambient light and create a subtle shimmer that reads as genuinely luxurious. Guests at two separate dinners asked if it was a much more expensive watch. One person guessed Cartier.

Exercise/Gym: Possible, but the 3 Bar rating means no water exposure. Keep it clear of pools, heavy sweat sessions, or any splashing. For gym wear, take it off or accept the risk.

Styling: Who Wears This Watch

The PD6628 Person

This watch is not for everyone. It's for a specific kind of person:

• The creative professional who uses their watch as personal branding
• The watch collector who wants something no one else has
• The confident dresser who isn't afraid of color and boldness
• The gift-giver who wants to leave an impression that lasts years
• The mechanical watch enthusiast who wants NH35 reliability with extraordinary presentation

What It Works With

✅ Dark suits (the red pops against navy, charcoal, black)
✅ All-black outfits (the watch becomes the only accent)
✅ Casual whites and neutrals (bold contrast)
✅ Smart casual (its natural home)
✅ Creative/fashion industry settings
✅ Evening wear

What It Doesn't Work With

❌ Conservative corporate (too bold)
❌ Formal traditional (size and style clash)
❌ Minimalist fashion aesthetics (fights the wardrobe)
❌ Physical outdoor activities (3 Bar limitation)

Value Analysis: Is $400 Justified?

This is the central question — and it's more nuanced than a simple yes/no.

What $400 Buys You

NH35 Movement: The movement alone, if purchased separately, costs $60-100. But NH35 in a $400 watch is different from NH35 in a $100 watch — the case, dial, and finishing quality that surrounds it matters enormously.

Sapphire Crystal: As established in the PAGANI DESIGN review, sapphire typically adds $50-100 to a watch's value.

Rotating Dial Mechanism: This is the genuine premium. A custom-engineered pusher-activated rotating dial is not a stock component. It's a unique mechanism that required design investment. You're paying for exclusivity here.

Red Diamond Dial: The faceted gemstone-inspired dial texture is a premium manufacturing element — not a printed flat surface.

NH35 + Leather + Stainless + Sapphire + Rotating Mechanism: At $400, you're paying for the sum of premium parts plus a genuinely unique design innovation.

The Honest Comparison

PD6628 vs. Standard NH35 Watch ($100-200): For $200-300 more, you get the rotating dial mechanism, the extraordinary red diamond texture, and the visual impact. If those things matter to you, the premium is justified. If you just want a good NH35 automatic, buy something at $150-200.

PD6628 vs. Swiss Dress Watch ($800-1,500): For $400-1,100 less, you get a more unique design, similar movement quality, and — honestly — more social impact. The PD6628 gets more comments than a plain-dial Swiss automatic at three times the price.

PD6628 vs. Other PINDU Models: PINDU builds a range of distinctive automatic watches. The PD6628 is the statement piece of the lineup — the one that goes furthest in artistic ambition.

Who Gets the Best Value

Best ROI: The watch enthusiast building a collection who wants one dramatically different piece. The PD6628 as a third or fourth watch — alongside a dress watch and a sport watch — adds something no other watch can.

Worst ROI: Someone buying their first and only watch. The 3 Bar limitation and bold styling make it a poor single-watch choice.

Key Specifications Summary

Pros & Cons

Pros

✅ NH35 automatic — world-class movement, self-winding, no battery
✅ Button rotating dial — genuinely unique, endlessly engaging
✅ Red diamond texture — extraordinary visual impact
✅ Sapphire crystal — scratch-proof protection
✅ Skeleton display — visible mechanical movement
✅ Stainless steel case — premium durability
✅ Premium leather strap — comfortable and well-matched
✅ Conversation starter — unmatched social impact
✅ 3-year warranty from PrimeTimepiece
✅ Hand-windable — doesn't need wrist movement to start

Cons

❌ 3 Bar water resistance — splash only, surprising at $400
❌ 16mm thickness — won't fit under dress shirt cuffs
❌ 47mm case — too large for smaller wrists
❌ Bold styling — not universally appropriate
❌ Not a daily beater — too precious for physical activities
❌ NH35 accuracy — ±10-20 sec/day vs quartz precision
❌ No date display — pure style, no calendar complication

Final Verdict: Art You Wear

Rating: 9/10 for what it is — a mechanical art piece that doubles as a watch

The PINDU PD6628 succeeds brilliantly at its actual mission: to be unlike any other watch you've ever worn, to command attention in any room, and to deliver genuine mechanical watchmaking in the most visually spectacular way possible. It is not trying to be a sports watch, a professional timepiece, or an everyday beater. It's trying to be extraordinary — and it is.

The rotating dial mechanism alone makes this watch worth the price of admission. There is nothing else like it at $400. There's nothing like it at $1,000. It's a genuinely unique horological experience delivered at a price point that makes it accessible to serious watch enthusiasts.

Rating Breakdown:

• Design: 10/10 (extraordinary, genuinely unlike anything else)
• Build Quality: 8.5/10 (excellent, docked slightly for 3 Bar)
• Movement: 9/10 (NH35 is excellent)
• Comfort: 8/10 (large and thick, but well-balanced)
• Value: 8.5/10 (justified for the right buyer)
• Versatility: 6/10 (niche styling, limited water resistance)

Buy This Watch If:

• You want a watch no one else will have
• You appreciate mechanical ingenuity as wearable art
• You dress confidently and boldly
• You're adding to a collection, not buying your only watch
• You want something that genuinely stops people in their tracks
• You're looking for a gift that will be remembered for years

Don't Buy This Watch If:

• You need an everyday all-purpose watch
• Water resistance is important to your lifestyle
• You prefer conservative, understated styling
• You want quartz precision in timekeeping
• You dress in formal/traditional settings primarily

Care & Maintenance

NH35 Automatic Care

Daily Wearing:
The NH35 winds itself through normal wrist movement. Wear it 8+ hours daily and it will stay fully wound and running continuously.

After Not Wearing:
If left unworn for more than 41 hours, the watch will stop. Before wearing, wind manually via the crown (30-40 rotations) until you feel resistance.

Servicing:
NH35 movements should be professionally serviced every 5-7 years. Service includes cleaning, lubrication, and regulation. Cost: $80-150 at a reputable watchmaker.

Setting the Time:
Pull crown to position 2 (fully out) to set time. The hacking feature stops the second hand for precise setting. Set to exactly :00 seconds by a reference clock, then push crown back in.

Protecting the Watch

Avoid:

• Water beyond splash/rain (3 Bar rated)
• Physical impacts (rotating mechanism is precision-engineered)
• Magnetic fields (affects NH35 accuracy — keep away from speakers, magnetic closures)
• Temperature extremes

Storage: Store in provided box or watch roll when not wearing. A watch winder is ideal for NH35 — keeps the movement wound and regulated when not on your wrist.

Leather Strap Care

• Condition with leather balm every 3-6 months
• Avoid saturating with water
• Store flat when not in use
• Replace every 2-3 years depending on wear

Sizing Guide

Wrist Size Recommendations

Under 6.5": Not recommended — 47mm will overwhelm
6.5" - 7.0": Wearable, bold statement
7.0" - 7.5": Ideal proportions
7.5" - 8.0": Perfect fit
8.0"+: Excellent — large wrist suits large watch

Frequently Asked Questions

Q: Does the rotating dial affect timekeeping?
A: No. The rotating dial is cosmetic — it sits above the movement and doesn't interact with timekeeping functions.

Q: Can I swim with this watch?
A: No. 3 Bar is splash-resistant only. No swimming, showering, or heavy water exposure.

Q: How does NH35 compare to Swiss automatic movements?
A: NH35 is Seiko's workhorse movement — extremely reliable and long-lasting, slightly less accurate than COSC-certified Swiss alternatives. For ±10-20 seconds/day, it's excellent.

Q: Is 47mm too big for everyday wear?
A: Depends on your wrist and style. For 7"+ wrists and bold dressers: no. For smaller wrists or conservative styles: yes, likely too large.

Q: Why is water resistance only 3 Bar at $400?
A: The rotating dial mechanism adds complexity that makes higher water resistance difficult to engineer. It's a genuine trade-off for the unique feature.

Q: How do I wind it manually?
A: Unscrew crown (if screw-down), pull to position 0 (no pull, just turn), and rotate clockwise 30-40 times.

Q: Will the button mechanism wear out?
A: After 2 weeks of heavy use, zero wear observed. These mechanisms are typically designed for thousands of operations.

Q: Is this watch good as a gift?
A: It's one of the best gift watches in the catalog — visually stunning, mechanically interesting, and truly memorable.

Alternative Recommendations

For Lower Price Automatic

PINDU Collection — Other PINDU automatics at various price points

For More Conventional Premium

PAGANI DESIGN PD-YS008 — VK63, sapphire, 100M — $149.97

For All Automatic Watches

Automatic Watch Collection — Full selection of mechanical timepieces

For Budget Entry Into Automatics

Watches Under $200 — Entry-level mechanical options

Where to Buy

Price: $399.99 USD
Available: PINDU PD6628 at PrimeTimepiece

Color Options: Red dial variant reviewed; check listing for additional options

Included with Purchase:

• 3-year warranty
• Free delivery
• Secure checkout
• 14-day returns

Conclusion: The Watch That Makes People Stop and Stare

The PINDU PD6628 Button Rotating Red Diamond Dial Automatic is the most genuinely unique watch in PrimeTimepiece's entire catalog. There is no other watch at any price point that offers this combination: a button-activated rotating dial, a gemstone-textured red diamond face, skeleton movement visibility, and a legendary NH35 automatic — all for $399.99.

Is it for everyone? Absolutely not. The bold size, bold color, and limited water resistance make it a specialty piece. But for the buyer who wants mechanical art they can wear on their wrist — for the collector who already has a sport watch and a dress watch and wants something that defies category — for the gift-giver who wants to create a moment that will be talked about for years — this is the watch.

You won't find anything like it. That's the point.

Own Something Truly Unique

Get the PINDU PD6628: Order Now

Explore More:

• All PINDU Watches
• All Automatic Watches
• All Watches
• Watches Under $200

Every Purchase Includes:

• 3-Year Warranty
• Free Shipping
• 14-Day Returns
• Secure Checkout

Questions? Contact Our Watch Experts

Review conducted over 2 weeks of daily wear including professional, casual, and evening settings by Cesar R for PrimeTimepiece. Watch provided for review. All opinions are honest and unbiased.