Rolex 5508 was in production approximately from 1958 to 1962, a run of approximately 4 years, carrying the 1530 automatic caliber in a 38 mm case rated to 100 meters.
The last small-crown Submariner before crown guards changed the case forever.
Dates carry a "c." because that is what honesty requires: Seiko's own archive gives only approximate production windows by caliber, so the file states the documented range and marks it as such rather than inventing precision.
The full collector's file for this reference — variants, dial codes, and the authentication walk-through — is on the writing schedule; the specifications above are the permanent record.
The Submariner is the most counterfeited watch on earth, and its vintage references add the assembly problem on top: service dials, swapped inserts, relumed hands and married cases circulate freely. The rules: serial era and part details must tell one consistent story, movement photos are not optional, red-letter and military claims carry the burden of proof, and at modern-classic price levels, route the purchase through a platform authentication program.
Production windows and specifications compiled from documented collector references and period catalogs, cross-checked across independent sources; manufacturer records for this era are approximate by Seiko's own account.