Per Rule,
“The extractor, breech bolt body, extractor ring/bolt stop extension and magazine follower were ‘jeweled’ or engine-turned, a common cosmetic treatment for SG rifles after 1954”.
The ‘SUPER’ barrel stamp was used on ‘browned’ barrels intended for SG’s after 1954.
The reversed ‘S’ stamp was frequently found on recoil lugs of receivers intended for SG’s from 1955 to 1959.
