The standard Rear Wheel Strap (what's in the box with the Talon, Mini Bomber, and Bomber racks) includes a Velcro strap for holding down your wheel. You can uprgade to a ladder strap and buckle for a more solid connection. The Rear Wheel Housing and Ladder Strap Upgrade comes with the ladders strap pre-assembled to the Rear Wheel Housing. Just replace your current housing and velcro on your Rear Wheel Strap and off you go.