3ttt stems were originally known as Ambrosio, which also made bars and rims, both in aluminum and steel. The Ambrosio "Champion" family goes back to at least 1953 (page 190 "World of Rebour"). The "Champion" was available in polished aluminum or chromed steel, and was still being sold as late as 1964 (Reliable Cycle catalog, 1964, page 42) Also available was the Ambrosio "Super Corsa" adjustable alu stem. The "Champion" came in 8, 9, 10, 11, and 12cm lengths. These stems were stamped "AMBROSIO CHAMPION" on top of the bulge where the bar passed through.

By 1963 Ambrosio had introduced the "Gran Prix" stem, which updated the "Champion" by eliminating the point at the rear, behind the edge bolt head (Evian Cycles catalog, 1963, page 43). This was soon updated again, to a recessed allen-key wedge bolt. Some of these stems included the text "MADE IN JTALY" (sic) on the right side, and "GRAN PRIX" on the left.

There was also a lighter version of the late Ambrosio stem, with wedge cuts running side-to-side on the base rather than front to back, and an I-beam section to the extension. This stem said "MADE IN ITALY" on the right, and "AMBROSIO SpA" on the left.

Sometime between 1964 and 1973 Ambrosio became TTT (Bike World Magazine, October 1973, page 18). In 1973, TTT still made the old Ambrosio adjustable, the Gran Prix with allen-head wedge bolt, and the "Record", which was lighter than the Gran Prix by 1 ounce! The Record had the extension length cast into the stem, and was available in 6.5, 8.5, 10.5, 11.5, and 12.5 mm lengths. By 1979 the Record stem has an allen-head bar clamp bolt, and came in sizes 60mm to 140mm in 5mm increments (International Pro Bike Shop catalog, 1979). The Record was the first to be anodized...the
others in the family had all been polished bare aluminum.

Wholesale for an Ambrosio "Champion" stem in 1964 was $2.65. By 1980 the retail price for a TTT "Record" stem had soared to $16.95!"
                                                                                                      Aldo Ross

From TTT anniversary press release May 17, 2011:

"3T, originally known as TTT, was founded by Mario Dedioniggi in 1961 in Torino. 3T handlebars and stems quickly became popular with Italian racing cyclists, and by 1970 they were in widespread use in the professional peloton. 3T was among the first cycle component manufacturers to switch production from steel to aluminum alloys. The firm worked closely with pro racers to refine handlebar design. 3T ‘bends’ took their name from the champions of the era – Merckx, Saronni, Moser, and Gimondi."

"In 2007 3T was bought from Gruppo concern by René Wiertz, a former senior executive of the Dutch multinational Philips. He has brought all his skill as a deal-maker and team-builder to restore the luster of the glorious but faded 3T brand, and transform it into a front-line player in the global business of cycle sport, together with Technical director Richard McAnish an expert structural engineer."