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Parts ranked by casing diameter

36.60 mm

ETA / Unitas 6497-1 has the highest casing diameter in the dataset, at 36.60 mm.

Which part has the highest casing diameter?

ETA / Unitas 6497-1, at 36.60 mm, tops the 90 parts we hold a published casing diameter for. The full ranking is below.

#	Parts	Casing diameter
1	ETA / Unitas 6497-1	36.60 mm
2	ETA / Unitas 6498-1	36.60 mm
3	Sellita SW400-1	31.00 mm
4	Miyota OS20	30.80 mm
5	Seiko VK63 (SII)	30.80 mm
6	Seiko VK64 (SII)	30.80 mm
7	Seiko VK67 (SII)	30.80 mm
8	ETA Valjoux 7750	30.00 mm
9	Sellita SW500	30.00 mm
10	Sellita SW510	30.00 mm
11	ETA 2834-2	29.00 mm
12	Ronda 5021.D	28.60 mm
13	Miyota FS00	28.60 mm
14	Ronda 5040.B	28.60 mm
15	Ronda 5030.D	28.00 mm
16	Ronda 4220.B	28.00 mm
17	Seiko NH35 (TMI NH35A)	27.40 mm
18	Seiko NH36 (TMI NH36A)	27.40 mm
19	Seiko 7S26	27.40 mm
20	Seiko 4R35	27.40 mm
21	Seiko 4R36	27.40 mm
22	Seiko 6R35	27.40 mm
23	Seiko NH34 (TMI NH34A)	27.40 mm
24	Seiko 4R34	27.40 mm
25	Seiko NH38 (TMI NH38A)	27.40 mm
26	Seiko NH70 (TMI NH70A)	27.40 mm
27	Seiko NH72 (TMI NH72A)	27.40 mm
28	Seiko 7S36	27.40 mm
29	Seiko 6R15	27.40 mm
30	Ronda 715	26.20 mm
31	Ronda 705	26.20 mm
32	Miyota 8215	26.00 mm
33	Miyota 8205	26.00 mm
34	Miyota 821A	26.00 mm
35	Miyota 9015	26.00 mm
36	Miyota 9039	26.00 mm
37	Miyota 90S5	26.00 mm
38	Ronda 6203.B	26.00 mm
39	Miyota 8200	26.00 mm
40	Miyota 8217	26.00 mm
41	Miyota 8245	26.00 mm
42	Miyota 8218	26.00 mm
43	Miyota 82S0	26.00 mm
44	Miyota 82S5	26.00 mm
45	Miyota 82S7	26.00 mm
46	Miyota 9011	26.00 mm
47	Miyota 9012	26.00 mm
48	Miyota 9019	26.00 mm
49	Miyota 9075	26.00 mm
50	Ronda 6203.D	26.00 mm

Data as of 2026-09-06.

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