Omega Speedmaster (Non-Moonwatch)

Most Omega Speedmaster (Non-Moonwatch) references take a 18 mm watch strap: 65 of 196. The lug width follows the case size: 38 mm case → 18 mm, 39 mm case → 18 mm, 40 mm case → 19 mm and 44 mm case → 21 mm.

Shop 18 mm Shop 19 mm Shop 20 mm Shop 21 mm Shop 22 mm

Omega Speedmaster (Non-Moonwatch) lug width by case size

196 references measured. Updated 2026-10-29.

Case	Lug width	References	Watch strap attachment	For example
38 mm	18 mm · 20 mm on 2	41	—	324.15.38.40.05.001, 324.15.38.40.10.001, 324.15.38.50.60.001
39 mm	18 mm	23	—	3113.30.00, 3113.53.00, 3123.33.00
40 mm	19 mm · 20 mm on 10 · 18 mm on 2	46	—	3210.50.00, 3210.51.00, 3210.52.00
41 mm	20 mm · 18 mm on 1	3	—	ST 176.0002 B, ST 176.0012
42 mm	20 mm	15	—	321.10.42.50.04.001, 327.10.43.50.01.001, 327.10.43.50.06.001
43 mm	20 mm · 21 mm on 2	7	—	3540.30.00, 3540.50.00, 3540.80.00
44 mm	21 mm · 22 mm on 7 · 20 mm on 1	60	—	304.23.44.52.06.001, 304.23.44.52.13.001, 304.30.44.52.01.001
45 mm	21 mm	1	—	522.50.45.52.03.001

References that take a different watch strap

324.33.38.40.04.001: 20 mm, not the 18 mm of most 38 mm cases
ST 186.004 Alaska: 20 mm, not the 18 mm of most 38 mm cases
323.10.40.40.02.001: 20 mm, not the 19 mm of most 40 mm cases
323.10.40.40.04.001: 20 mm, not the 19 mm of most 40 mm cases
323.21.40.40.01.001: 20 mm, not the 19 mm of most 40 mm cases
326.30.40.50.04.001: 20 mm, not the 19 mm of most 40 mm cases
326.30.40.50.06.001: 20 mm, not the 19 mm of most 40 mm cases
326.32.40.50.04.001: 20 mm, not the 19 mm of most 40 mm cases
3513.20.00: 20 mm, not the 19 mm of most 40 mm cases
3513.33.00: 20 mm, not the 19 mm of most 40 mm cases
3513.50.00: 18 mm, not the 19 mm of most 40 mm cases
3513.53.00: 18 mm, not the 19 mm of most 40 mm cases
3516.20.00: 20 mm, not the 19 mm of most 40 mm cases
3519.50.00: 20 mm, not the 19 mm of most 40 mm cases
ST 176.0002: 18 mm, not the 20 mm of most 41 mm cases
304.30.43.52.01.001: 21 mm, not the 20 mm of most 43 mm cases
304.30.43.52.06.001: 21 mm, not the 20 mm of most 43 mm cases
311.30.44.50.01.001: 22 mm, not the 21 mm of most 44 mm cases
321.30.44.50.01.001: 20 mm, not the 21 mm of most 44 mm cases
321.30.44.52.01.001: 22 mm, not the 21 mm of most 44 mm cases
321.30.44.52.01.002: 22 mm, not the 21 mm of most 44 mm cases
321.33.44.52.01.001: 22 mm, not the 21 mm of most 44 mm cases
321.53.44.52.01.001: 22 mm, not the 21 mm of most 44 mm cases
321.58.44.52.51.001: 22 mm, not the 21 mm of most 44 mm cases

And 1 more in the full list below.

Questions about the Omega Speedmaster (Non-Moonwatch)

Do all Omega Speedmaster (Non-Moonwatch) case sizes take the same watch strap?

No. The lug width changes with the case size: the 38 mm case takes 18 mm, the 39 mm case takes 18 mm, the 40 mm case takes 19 mm, the 42 mm case takes 20 mm and the 44 mm case takes 21 mm. Check your case diameter before you buy.

Can two Omega Speedmaster (Non-Moonwatch) watches with a 44 mm case take different watch straps?

Yes. Of the 60 Omega Speedmaster (Non-Moonwatch) references with a 44 mm case, 52 take 21 mm, 7 take 22 mm and 1 take 20 mm. The reference number decides, not the case size alone.