If you roll with a Cervélo P2, P3, or P4 and want to have access to the most reliable single bottle rear hydration, then the XLAB Delta 300 Rear Hydration System will work for you. It has been specially designed to mount directly onto seat posts with two holes at the rear. Super aero and secure, you’ll never have to worry about launched bottles. Aside from the Cervélo line, the Delta 300 accommodates bikes that use the ISM Adamo saddle with a transition hook. The Quintana Roo PRsix is also compatible with the Delta 300. If you are all about getting in the miles so that you can be super ready on race day, the XLAB hydration systems will work to help you stay on track and well-watered through the hot summer months. By mounting the Delta 300 directly onto the seat post, it will stay in your draft and can even increase the effectiveness of your aero position by filling in the void behind you, smoothing out your airflow. It is a strong, sturdy mounting so that you won’t feel any sway in the back, and it will be able to withstand the abuse rear racks can take in the transition sections of races. XLAB uses Loctite and locknuts, to ensure that the screws are locked in place safely and securely. Using Loctite also means that you won’t be subjected to a lot of noisy hardware vibrations even over the roughest roads. The funnel-shaped cage allows for easy access to your bottle. Using the Gorilla XT Cage is bringing out the heavy artillery since the XT version has twice as much grip as the regular XLAB Gorilla cage has. Its tall gripping sides and 14 pounds worth of grip strength makes this just about the strongest carbon bottle cage on the market. Whether you want to hide your bottles from the wind, or carry an extra rear bottle to refill your Torpedo Aero Bar water bottle, the XLAB Delta 300 Rear Hydration System will give you the option of being able always to have your favorite drink mix without stopping at the gas station in the middle of nowhere. It comes with an XLAB Cage Mount and a Gorilla XT Cage.