Vittoria's Removable Valves are something special. They're not valve extenders like you'd expect, but actually valve stems that function with Vittoria's 320 TPI tubulars and Rubino Pro tubulars. These tires and tubes have unique removable stems. Simply un thread the valve stem that is not the preferred length for your rims and screw on a new one. This way, you can ensure that you have a single piece stem at the proper length for easy inflation and with an accessible valve. With an exposed valve, you'll be able to tighten it to prevent leaks or open it fully to inject liquid sealant inside the tubular tires on your deep carbon rims. While this may not sound revolutionary, you'd know different if you ever had a leaking or stuck valve inaccessible inside the confines of your rim and were faced with the prospect of ripping off your perfectly glued race day tubulars. The Vittoria Removable Valves are available in three lengths 42, 60, 80 and 110mm. They're sold as a pack of 2, enough for one complete bike. Please Note: These will NOT thread onto the ends of your existing presta valve stems to act as extenders.