Specifications： Color: Black Size: 26" Bike Material: Carbon Steel Seat Material: Synthetic Leather, Metal, Sponge Tire Material: Rubber Frame Structure: Folding Bike Frame Type: Rigid Frame Front Fork Type: Oil Spring Fork Brake System: Double Disc Brakes Adjustable Seat Height: 80-95mm / 3.1-3.7inch Chain Length: 108 Knots Gear Size: 24/34/42t Three-part Number of Speeds: 21 Speed Package Included: 1* 26" Folding Mountain Bike.