This "self-adhering" version of the ThumbRocker was created because of customer requests. Its a 3D printed piece and uses "double sticky" tape to mount. This allows you to mount it anywhere on your bass that youd like. 

This is a universal fit, but popular with the Fender Jazz bass.

Please use your own discretion when mounting. Theres no guarantee about the adhesive reaction on your bass. It may be difficult to remove, and /or may affect your bass finish.