Upgrading your bike to a Inter-3 is very simple. Switch your wheels, mount the grip shifter to the handle bar and attach the cable. That's it! Or, take it to your local bike shop. Most shops will mount your kit or even lace the hub to your existing wheel for a reasonable charge. SHIFTER & CABLE: Shimano Revo Shift REAR HUB: Shimano Nexus Inter-3, 120mm OLD (width) FRONT HUB: Rust Proof Machined Alloy 100mm OLD (width) RIMS: Weinmann AS7X 6061 - T6 Aluminum Alloy 26 "x1.75"-2.125" 36 Spoke BRAKE: Shimano Coaster SPOKES: Stainless Steel 14G FREEWHEEL: 18 teeth