1959–196213 variants
Second Speedmaster, with a black bezel insert and alpha hands on the same straight-lug mid-case as the 2915. Eight sub-references (-1 to -6, -61, -62). Wally Schirra’s privately bought 2998 flew on Sigma 7 in 1962, the first Omega in space.
Faded ends mark approximate or unknown dates. Years are as stated by the cited sources.
Specs shared by all variants. Variant pages show where a variant differs.
Like the -1, with the Base 1000 bezel and short subdial markers; both kinds of “O” are seen.
Changes the dial and hands: longer markers, lower “Swiss Made” (A5-type dial) and a black Base 500 “dot over ninety” bezel.