Diamondback Overdrive 29'er Mountain Bike (2011 Model, 29-Inch Wheels), Satin Black Oversized mountain bike with 29-inch butted aluminum frame SR Suntour XCT MLO fork with 100mm travel and mechanical lockout SRAM X-4 rear derailleur with 24 gears and 8-speed trigger shifters Tektro Novela mechanical disc brakes; 29-inch WTB Prowler SL tires Double-wall rims; available in 16-, 18-, 20-, and 22-inch sizes