Specialized Inner Tubes The original and still the best value bicycle suspension - the inner tube The inner tube was probably invented in Scotland the century before last Specialized tubes stand out for their consistent quality, light weight, reliability, and reasonable price Schrader means the car-type valve usually found on budget mountain bikes and BMXs. Presta means the skinny type of valve with a nut on top which you have to undo to get air into or out of the tyre, as found on near any better quality road or mountain bike Tube Guide - to find out what size of tube you need, check the size embossed on the side of the tyre. Please also note that you often get a choice of valve stem lengths. For instance skinny 700c road bike tubes are available with 40, 48 60 or 80mm stems. You'll need a longer stem if your bike has deeper aero wheel rims. Check the wheel's original tubes valve stem to verify what size you'll need. 12, 16, 20 and 24" tubes suit smaller wheel bikes inc kids' bikes 26 x 1.0-1.15” Presta or Schrader: 95g. For skinny ATB tyres and some 26" wheel road bikes 26 x 1.25-1.5” Presta or Schrader: 150g. For medium-sized ATB and 26" hybrid or touring bike tyres such as the Specialized Nimbus 26 x 1.25-2.0” Presta or Schrader: 175g. For 'standard' MTB tyres 26 x 1.75-2.4” Presta or Schrader: For wider MTB tyres 26 x 2.3-3.0” Presta or Schrader: For wider still plus-size MTB tyres 26 x 3.8-4.8” Presta: For Fattie MTB tyres. 29 x 1.75-2.4" Presta or Schrader: For 29er MTB tyres 29 x 1.9-2.3" Presta or Schrader: an alternative for 29er MTB tyres 650B x 1.75-2.4" Presta or Schrader: For 27.5" MTB tyres 650B x 2.4-3.0" Presta: For fatter 27.5" MTB tyres 700 x 18-25 Presta: For skinny road bike tyres 700 x 20-28 Presta: For most road bike tyres 700 x 28-38 Presta or Schrader: For wider road bike tyres inc. many cross, touring, hybrid and adventure bikes 700 x 32-50 Schrader: For wider still road bike tyres inc. many cross, touring, hybrid and adventure bikes For our complete range of tyres, puncture repair and prevention please click here.