Challenge's Gara Open Tubular (Clincher) is light enough to race on, and durable enough for training, too. It's hand made on their lightweight 240tpi SuperPoly casing with a long-wearing tread compound and tough polyester in the sidewalls. The center tread is made to roll quickly, while the side tread sticks to the road in the corners.
This is a folding clincher tire.
700 x 23c