MonsterKing New Bicycle Bike 3 x 7 Speed Shift-Shifter Brake Lever Combo for Mountain Bike

Features: 21-speed transmission,ergonomic design of position and trigger handle. Make transmission easier operation, lower division, visualization of the gear display, speed changes at a glance. Easier operation,lower division. Specifications: Condition:100% Brand New Compatible for:Front 3 gear, Rear 7 flywheel and 21 speed positioning transmission system Scope of application: 21-23mm diameter handle bar Package includes: 2pcs Transmission (Left 3 speed / right 7 speed), 2pcs Brake line