XLab Delta Wing 400 Fits saddles with standard rails Includes Cage Mount and Gorilla XT water bottle cage Includes space for repair item storage To ensure the best possible fit with the Gorilla XT Cage, use a bottle with a uniform groove all the way around and fits tightly into the hook at the top (bottles with short groves like the The Delta Series are saddle mounted single bottle systems. Mounting a bottle to saddle rails rather than traditional frame mounts has been proven to cut down on aerodynamic drag.