The R'AIR race tube gives you all the ride advantage of latex with all the functionality of butyl. And you can still patch it with a regular butyl patch kit. With these exceptionally light yet still tough inner tubes, your clincher tires will roll a bit easier. Presta (also called French or Sclaverand) valve.
Available in following sizes:
700x18/23C - Presta veltil 48 mm (66 g!)
700x23/28C - Presta veltil 34 mm (76 g!)
700x31/35C - Presta veltil 48 mm (113 g!)