Bell SELF-SEALING ULTRALIGHT Tube 26-Inch x 1.90 Presta No flats, guaranteed! Performance mountain bike tube 20% lighter than Bell self-sealing inner tubes Liquid sealant inside tube flows to seals most holes up to 1/8 inch instantly while you ride Lasts the life of the tire Tube sealant will not freeze or dry out Seal punctures as they happen Fits 1.75 inch  2.25 inch