Do you have deep cross-section rims? When you air up your tires, is it a headache to get your pump to "bite" on the end of the presta valve? The Zipp Valve Extender is the answer. The extender threads onto the end of your valve to give your pump more surface area to grab ahold of. These are black anodized with a laser etched Zipp logo and a 3mm hex key fitting in the pump head end.

Will fit any presta valve stem, and works with both clincher and tubular tires. Two sizes, Small for rims up to 40mm in depth, and Large for rims up to 60mm. And remember -- before installing these, make sure to open the valve on your tube by unthreading the tip of the valve! Also, please note that the price is per extender, not for a pair.