Replica Watch Movements Explained — NH35, ETA, Cloned Calibers

Stewart Charette, watch industry analyst, holding a brass loupe at a watchmaker’s workbench

Stewart Charette· 8 years in the watch community

Updated May 5, 2026

Movement choice is upstream of almost every other quality decision in replica watches. The movement determines whether the watch passes through a sapphire case-back, how reliably it keeps time, how serviceable it is at independent watchmakers, and how much the watch costs. This guide explains the four classes of movements you'll encounter — Asian base, Swiss base, cloned Swiss, and cloned proprietary — and which one belongs in the watch you're about to buy.

I'll cover what each movement type is, where you'll find them, what they cost, and the buying decision they enable. By the end, you should be able to read a dealer listing and immediately understand what kind of movement is in the watch.

The four movement classes

In rough order of quality and price:

Asian base movements. NH35, DG2813. Reliable, cheap, visually wrong for any specific brand.
Swiss base movements. ETA 2824, ETA 2836. Better tolerances, still generic.
Cloned Swiss calibers. VR3135, cloned 8500, cloned 4130. Engineered to match a specific genuine caliber.
Cloned proprietary calibers. VR3186, cloned 324 SC, cloned 3120. Engineered to match a brand-specific caliber the brand owns exclusively.

Each class has appropriate use cases. The mistake is putting the wrong class in the wrong watch.

Class 1: Asian base movements

Asian base movements are mass-produced calibers from Japanese (Seiko/TMI) or Chinese manufacturers, used as the engine in budget watches across the world (microbrands, fashion watches, and budget replicas).

NH35 / NH36

The most common replica movement at the budget tier.

Manufacturer: Seiko (TMI subsidiary)
Architecture: Automatic, hacking, hand-winding
Power reserve: 41 hours
Frequency: 21,600 vph (3 Hz)
Jewels: 24
Accuracy: ±20 seconds/day typical, variable
Service complexity: Low — any independent watchmaker can service
Price tier: Cheapest movement option

Where you'll find it:

Most Noob Factory production (Submariner, Daytona, Datejust)
Generic Chinese replica brands
Microbrands (legitimate watch brands using NH35 as their movement)

Visual accuracy: The NH35 has Seiko's bridge layout, rotor design, and finishing — none of which match Rolex 3135 or any other Swiss caliber. Through a sapphire case-back, an NH35 in a Submariner is immediately wrong.

When NH35 is acceptable:

Closed case-back wear (NH35 invisible)
Budget priority over visual accuracy
Reliability priority over ornamentation

When NH35 is not acceptable:

Sapphire case-back display (visually wrong)
High-tier Rolex sport replicas (mismatched with case quality)
Any AP, Patek, or Omega replica (these brands have specific cloned calibers)

DG2813

Lower-tier Chinese automatic movement, similar to NH35 but with looser tolerances.

Power reserve: 40 hours
Frequency: 21,600 vph (3 Hz)
Accuracy: ±30 seconds/day typical
Use: Entry-tier replicas only

If you see DG2813 in a listing, the watch is in the entry tier. NH35 is preferable at similar price.

Class 2: Swiss base movements

Swiss base movements are mass-produced Swiss calibers, primarily from ETA (a Swatch Group subsidiary) and Sellita. They're the standard in mid-tier Swiss watches and microbrands using genuine Swiss movements.

ETA 2824

The workhorse. Used in countless mid-tier Swiss watches and some replicas.

Manufacturer: ETA SA (Swiss)
Architecture: Automatic, hacking, hand-winding
Power reserve: 38–42 hours
Frequency: 28,000 vph (3.9 Hz) or 28,800 (4 Hz)
Jewels: 25
Accuracy: ±5–15 seconds/day typical
Price tier: Mid

Where you'll find it:

Some replica watches (less common in current production)
Mid-tier Swiss-made watches (Tissot, Hamilton, etc.)
Vintage replica production

Visual accuracy: The ETA 2824 has Swiss bridge layout closer to Rolex 3135 than NH35 is, but still distinct. Some replicas use ETA 2824 with custom decoration to approximate specific Swiss calibers — this is a hybrid approach that has largely been replaced by cloned calibers.

When ETA is acceptable: rarely in current replica production. Most replicas have moved to either cheaper Asian base (NH35) or more expensive cloned calibers. ETA replicas are mostly historical.

Sellita SW200

Sellita's clone of ETA 2824. Used after Swatch Group restricted external ETA sales around 2010.

Functionally equivalent to ETA 2824
Slightly different bridge layout
Similar accuracy and reliability

Same use cases as ETA 2824 — present in some older replicas, less common now.

Class 3: Cloned Swiss calibers

Cloned Swiss calibers are Chinese-made movements engineered to match specific Swiss calibers visually and functionally. The architecture, bridge layout, and finishing are designed to approximate the cloned caliber as closely as production allows.

VR3135

The benchmark cloned caliber. Produced primarily by Clean Factory.

Clones: Rolex Caliber 3135
Used in: Rolex Submariner replicas, Sea-Dweller, Datejust
Manufacturer: Clean Factory and similar Chinese producers
Power reserve: 48 hours
Frequency: 28,800 vph (4 Hz)
Jewels: 31
Accuracy: ±5–10 seconds/day typical
Visual accuracy to genuine 3135: High through case-back

Significance: VR3135 was the movement that brought Rolex Submariner replicas into super-clone tier. Through a sapphire case-back, VR3135 reads as a Rolex 3135 to non-experts. Expert inspection identifies tooling marks and finishing differences, but the silhouette is correct.

VR3235

Newer cloned Rolex caliber, used in 2020+ Rolex production.

Clones: Rolex Caliber 3235
Used in: Late-2024+ Submariner 41mm 126610LN, Datejust 41 126334
Power reserve: 70 hours (extended from 3135's 48 hours)
Frequency: 28,800 vph (4 Hz)
Jewels: 31
Accuracy: ±5–10 seconds/day typical (with some early-batch QC issues now resolved)

Significance: VR3235 is the movement to look for in modern Rolex sport replicas. Clean Factory's Q1 2024 production had hairspring issues; Q4 2024+ production is consistent.

VR4130

Cloned Rolex chronograph caliber.

Clones: Rolex Caliber 4130
Used in: Daytona 116500LN replicas, 116508
Power reserve: 72 hours
Frequency: 28,800 vph (4 Hz)
Jewels: 44
Significance: column-wheel chronograph construction visible through case-back

VR4130 is the chronograph equivalent of VR3135. Pushers actuate cleanly, sub-dial alignment is consistent, reset hands are accurate. The vertical clutch on genuine 4130 is approximated rather than replicated.

Cloned 8500 / 8800 (Omega)

Cloned Omega Co-Axial calibers, produced by VSF Factory.

Clones: Omega Calibers 8500 and 8800 (Co-Axial)
Used in: Seamaster Diver 300M (8800), Planet Ocean 600M (8500)
Power reserve: 55 hours (8800), 60 hours (8500)
Frequency: 25,200 vph (3.5 Hz)
Jewels: 35–39

Significance: Co-Axial is Omega's signature escapement. The cloned 8500/8800 are the only credible Co-Axial reproductions in the niche; lower-tier Omega replicas use Asian-base movements that are visually wrong.

Cloned 1861 (Omega Speedmaster)

Manual-wind chronograph clone for Speedmaster Professional.

Clones: Omega Caliber 1861 (manual-wind)
Used in: Speedmaster Pro Moonwatch replicas
Power reserve: 48 hours
Frequency: 21,600 vph (3 Hz)
Jewels: 18

The 1861 is itself a 1968-era movement with mechanical austerity that's actually easier to clone than modern automatic movements. VSF's cloned 1861 is consistently rated as the closest in the niche.

Cloned 3120 (AP Royal Oak)

Cloned AP automatic caliber.

Clones: AP Caliber 3120
Used in: Royal Oak 41mm replicas
Manufacturer: ZF Factory primarily
Power reserve: 60 hours
Frequency: 21,600 vph (3 Hz)
Jewels: 40

Significance: Visible through sapphire case-back on AP Royal Oak replicas; Côtes de Genève finishing on bridges; rotor decoration approximating AP signature pattern.

Cloned 324 SC (Patek Nautilus)

Cloned Patek automatic caliber.

Clones: Patek Philippe Caliber 324 S C
Used in: Nautilus 5711 replicas
Manufacturer: ZF Factory primarily
Power reserve: 45 hours
Frequency: 28,800 vph (4 Hz)
Jewels: 29

Significance: Visible through case-back on Nautilus replicas; Patek-style rotor decoration; date complication.

Class 4: Cloned proprietary calibers

The hardest tier. These movements clone proprietary calibers that the brand owns exclusively, with technical challenges that other factories haven't solved.

VR3186 (Rolex GMT-Master II)

The standout proprietary caliber clone — the only true GMT clone in the niche.

Clones: Rolex Caliber 3186
Used in: GMT-Master II replicas (126710BLNR, 126710BLRO, 126711CHNR)
Manufacturer: Clean Factory exclusively
Significance: Independently-jumping hour hand via crown middle position. Lower-tier GMT replicas use 24-hour disc methodology that requires manual realignment — visually wrong.

Why it's special: the VR3186 is the only cloned movement in the niche that successfully replicates a true GMT mechanism. Clean Factory invested in this tooling alone; other factories have not pursued it. Any GMT-Master II replica without VR3186 is visually wrong on the hour-hand jump function.

Cloned vs base: the buying decision

The choice between cloned and base movement determines:

Factor	Cloned caliber	Base movement
Sapphire case-back visual	Correct	Incorrect
Closed case-back	Same as base	Same as cloned
Service cost	Higher (specialist needed)	Lower (any watchmaker)
Reliability	Comparable	Comparable
Price	$200–500 premium	Lower
Long-term parts	Variable	Always available

Use cloned for: sapphire case-back display, high-tier brand replica (AP, Patek, Omega), credible visual fidelity to genuine.

Use base (NH35) for: closed case-back wear, budget priority, daily-wear with disposability, first replica to test the niche.

Movement-specific quality flags

When inspecting a replica, watch for these movement-specific issues:

For NH35: the rotor architecture is identifiable in seconds — Seiko's signature pattern. Don't pay for cloned-Swiss prices on NH35 watches.

For VR3135: check the crown winding mechanism — VR3135 should have smooth detents at hand-set and date-set positions. Grinding suggests a base movement repackaged.

For cloned 8500/8800: the Co-Axial escapement is the visual signature; if the escape wheel doesn't have Co-Axial geometry, it's a base movement.

For VR3186: test the GMT function. Crown middle position should jump the hour hand independently, not advance the entire dial.

How to verify movement on order

Before payment:

Specify the movement designation in writing on the order: "Movement: VR3135" or "Movement: cloned 8800."
Request sapphire case-back QC photos if reference normally has sapphire case-back.
Reference the specific cloned caliber spec (power reserve, frequency, jewels) in the order — discrepancies between order and delivery are warranty grounds.
For chronographs, request video of pusher actuation and reset alignment.

After delivery:

Set the watch and check accuracy over 7 days. Cloned calibers should run within ±10s/day. NH35 may run ±20s/day. Wildly off accuracy is a movement issue.
Test winding — should have smooth detents. Grinding suggests issue.
Test crown positions — winding (out one click), date (out two), hand-set (out three on Rolex-style movements).
For sapphire case-back models, photograph the movement and compare to genuine reference photos online.