Prestacycle Cycling EZ-Grip Big Presta Head (Urethane), Bike Pump Accessoires COMPATIBILITY - Perfect for Tubeless tires, valve extenders and any Presta valve. INCLUDES - newest version of the Mini Presta Head Gasket using Urethane Elastomer. QUALITY - It lasts more than 5 times longer, gives a better seal and flexes to work anywhere along the Presta shaft for any Presta application. ADVANTAGE - Allows high-flow inflation with the valve core removed for seating tires. QUALITY: Prestacycle isdedicated to putting new ideas and innovations in the hands of cyclists. As life-long cyclists, we understand its about riding and actually being on the ride. We make products to do the right job quicker, and give you more time in the saddle. Urethane Elastomer Grommet is softer and stronger.L asts more than 5 times longer than rubber.S afe for all types of Presta valves, including tubeless and tubeless-conversion valves.W ill not harm newer lightweight performance valves.M ade with 6061-T6 Alloy  Strong as Brass and only 1/3 the weight.P atent-pending 2-way connector screws onto the Prestaflator threaded connector or directly clamps to a hose.