The specialized 26in presta fat bike inner tube is a must have for all fat bike riders it39s the perfect replacement or spare tube for when you get a flat the tubes have been moulded for a consistent thickness of butyl rubber which is particularly impressive considering it39s massive 38 48 width capabilities specialized 26in fat bike inner tube features design for 38 48 tyre widths long 40mm presta valve for fast amp easy inflation moulded construction method fo