Pure Fix Keirin Track Double-Butted 6061 Aluminum Bike Frameset Double-butted 6061 aluminum frame and fork designed to perform on the streets, the velodrome, and everywhere in between Includes integrated headset, 31.8mm seatpost clamp, smooth welds, and 68mm English threaded bottom bracket Light, responsive, quality frame at an affordable price Available in sizes: 49, 52, 55, 58 and 61 centimeters; framesets weigh 4 lb 8 oz to 5 lb 4 oz