MovementSwap

Home / Research / The parts most likely to need an adapter

The parts most likely to need an adapter

81%
Miyota 8215 needs an adapter or does not fit in 81% of the combinations we checked, the highest share in the dataset.

Which part most often needs an adapter?

Miyota 8215 tops the list: 22 of its 27 checked combinations (81%) need an adapter or do not fit. The full ranking is below.

#PartsAdapterNo fitAdapter-or-no rate
1Miyota 821516681%
2Miyota 820516681%
3Miyota 901516681%
4Miyota 903916681%
5Miyota 821A14680%
6Miyota 90S514680%
7ETA 2824-217387%
8ETA 2836-217286%
9Sellita SW260-1190100%
10Sellita SW290-1190100%
11Sellita SW200-117186%
12ETA 2892-A217186%
13Sellita SW220-117085%
14Sellita SW300-117085%
15ETA 2801-217085%
16Sellita SW210-117085%
17ETA 2804-217085%
18Sellita SW215-117085%
19Sellita SW216-1170100%
20Seiko 6R3567100%
21Seiko NH35 (TMI NH35A)4880%
22Seiko 7S2666100%
23Seiko NH36 (TMI NH36A)4779%
24Seiko 4R354677%
25Seiko 4R364677%
26Ronda 5153043%
27Sellita SW51030100%
28Ronda 6004.B2040%
29ETA 2834-211100%
30ETA 267111100%
31ETA 268111100%
32Ronda 6203.B11100%
33Ronda 5030.D02100%
34Ronda 5021.D02100%
35Ronda 71511100%
36Ronda 513S1020%
37ETA Valjoux 77501025%
38Sellita SW5001025%
39Ronda 4220.B01100%
40Ronda 76301100%

How this is worked out

For every part we counted the combinations that resolve to an adapter fit or a no-fit across the reference set, and ranked by that count. The rate is those combinations divided by all combinations checked for that item.

Data as of 2026-09-05.

Republish this

This table is free to reproduce with a link to MovementSwap. Embed the live version:

Related studies