At only 65g each (approx 50% lighter than a regular tube), Panaracers R-Air ultralight innertubes weigh less than many latex inner tubes. The R-Air 700c tubes are produced with a special Butyl compound, so unlike latex or other manufacturers lightweight tubes R-Air tubes do not loose air and do not sacrifice puncture resistance. Key Features: 3 valve lengths for suitability with various top end wheel sets for the weight conscious roadie.Size: 700c x18-23cValve lengths (32mm, 48mm, 60mm)