ETC's Inner Tubes are made from a high quality Butyl Rubber with a thickness of 1mm to provide a strong and consistent level of perfromance in cycling applications. This version of the inner tube is designed for 27.5" sized wheels with a presta valve hole.. • Size - 27.5x1.95-2.35". • Valve - 48mm Presta. • Wall Thickness - 1mm. • Construction - Butyl Rubber. • Available in a pack of 1, 2, 3, 4, 5, or 10 to suit your needs.