Blue (rare) Gen 1 1954 (Z-3) & Red Gen 2 1958 (D-2) w/vertical knurling. 54 Super Speed (Z-3 & Z-4) sold only w/Blue "TV" Special case last 6 months of 54 then production ended. In 54 the (50's style Gen 2) "Flair tip" Super Speed was also introduced so Gillette had 2 Super Speed sets that year.
