Prestacycle Pro Presta Head A Perfect Seal Proper tire inflation is important when it comes to riding a bicycle. With your tires properly inflated, you'll have fewer flats and your bike will roll more efficiently. The Prestacycle Pro Presta Head has an auto-lock mechanism that grabs onto the Presta pin without pulling or twisting. A seal is made on the top of the Presta valve, and the pin is pressed for 2 way flow/pressure reading. Easy-grip sides make it simple to press the side button, which fully releases the connection. Instant low-loss disconnect ensures tire pressure is exactly what you put in there. Features Steel/alloy construction is pro shop durable"L" design works on most automotive wheels Auto-lock mechanism grabs onto the Presta pin without pulling or twisting Safest head for all types of Presta valves including tubeless and tubeless-conversion valves Durable steel body protects the head from drops | Prestacycle | Pro Presta Head Presta/scv