Half a million snowmobiles were produced in 1972 during the boom years of the early snowmobile industry. Bombardier was the undisputed leader in the field, selling more snowmobiles than any other brand. It also had the largest dealer network in North America.
The 1972 T’NT snowmobile was already the well established favorite with riders who wanted speed on the trails or the race track. New in 1972 was a two-cylinder engine, which was more powerful and produced fewer vibrations. Also new, on both the T’NT and Blizzard models, was an emergency kill button on the right handlebar.
T’NT models included the 292, 340, 400, 440, 640, and 775, with the little single cylinder 292 the shortest (99 inches long) and lightest (316 pounds). The 775 with its 18 inch track was only an inch longer, but weighed in at more than a hundred pounds heavier at 440 pounds. Price-wise, the 292 T’NT cost $950 (CDN) and the 775 was priced at $1595 (CDN)
The 1972 Ski-Doo T’NT hood colors were also new — with black and white replacing some of the traditional bright yellow of the Ski-Doo line-up. Although available only to racers, the 1972 T’NT was the first Ski-Doo snowmobile with an optional free air-cooled (F/A) engine.

Photo credit: Taken by Linda Aksomitis at the 6th Annual Vintage Snowmobile Round-Up in West Yellowstone in March, 2009.
References:
Bombardier Inc, & Fondation J. Armand Bombardier. (1999). Ski-Doo, as long as there’s winter–. [Valcourt, Quebec]: Fondation J. Armand Bombardier.