Omega® Miscellaneous Case Parts, calibres: 640, yellow crown nut
yellow crown nut (slotted) for Omega 640 back wind. , head dia. 2.00 mm, female thread, total height 1.46 mm
* H. & W. Perrin Company Limited is independent of and not affiliated with or sponsored by Omega®. Omega® warranty does not apply to parts supplied by H. & W. Perrin Company Limited. Using generic parts may devalue your watch.