Enabling the tyres on your deep-rimmed wheels to be inflated without having to stretch the valve-heads, these Birzman valve extenders bring the valve heads within easy reach for precise inflation. This valve extender is compatible with Presta valves. Simply remove the valve core and the aluminium-made extender ensures a reliable flow of air and comes supplied with a valve core removal tool for easy setup and maintenance. Specification Material: CNC machined aluminium. 20mm (BM13-PO-AVE-20-SET) / 40mm (BM13-PO-AVE-40-SET) / 80mm (BM13-PO-AVE-80-SET).