Aerodynamic wheels are a godsend when it comes to speed: The reduction in wind drag they gain you is exponentially tied to your speed, and no one who's serious about training or racing would be caught dead without them on a ride that really counts. Nobody but nobody disputes their performance value, and in fact the only criticism anyone would ever throw out there is how tough it is sometimes to air the darn things up. Whether you've got 25mm deep Mavic Ksyriums or 58mm deep Zipp 404s, it's all-too-common for air to leak out of the typical thread-on-the-outside style valve extenders. If the tiny o-ring and the base of the extender is torn or if you didn't put just enough plumbers tape on the threads of the tube valve itself, you'll hear "psssssssssssssssssst" as soon as your pump hits 90psi and you never know how much air ends up really leaking out and what your pressure really ends up being once you're done pumping.

Tufo brought innovative thinking to the flawed universe of valve extenders. Rather than threading on the outside of your tube's valve, with the Tufo extender you'll actually unthread your existing presta valve, insert Tufo's extender, then thread the valve into the tip of the extender. You're literally building a seamless extension of your existing valve, so your days of leaks are over. It's a brilliant solution, especially for tubular tires.

The extenders are available in 20mm, 28mm, and 40mm. Add this length to the length of your existing valve and you'll know how long the valve will ultimately be. Two notes: (1) These extenders are compatible only with clincher tubes and tubular tires that have removable valve cores. Based on our research, every tube and tire we sell is compatible except for Michelin's clincher tube. (2) The extender is built with tiny wrench flats built to work with Tufo's valve tool. We sell this tool, and it costs just a couple of dollars. Do yourself a favor and buy the Tufo tool along with the extenders. It'll make the installation process easier and surer.

These extenders are sold per extender, so please buy two to equip a set of wheels.