Speedmaster transitional case backs between "Hippocampus" and "Medallion" (ca. 1970-73)
It looks like Omega experimented with the Speedmaster case-back transition from the pre-moon "Hippocampus" to the final "Medallion" version with three transitional variants: - the straight writing (Ref 145.022-69) - the straight writing - Apollo XI 1969 (...
