This thread is a summary of key additions and removal of these items from the market for sale. Dates are approximate. I am not including source materials that back these dates up because frankly I am too lazy to do the editing needed right now but the dates can be independently verified using a source like newspapers.com In the beginning the first instances of injectors (blades only) and Techmatic razors happens in 1964. The Techmatic razors were only sold in a trial market in Buffalo, NY before being sold nationally in 1965. Techmatic razors enjoyed a suprisingly long run from 1965 - 1984 and by mail order only in 1985-??. The Gillette injector blades in their various incarnations sold from 1964 - 1984 with them and Schick introducing Twin injector blades in 1973. The introduction of the Trac II twin injector blades coincides with Gillette introducing their first injector razor. From 1973 - 1975 the razor was branded as a Trac II twin injector, from 1975 - 1980 it was branded as a Twinjector.