Surly Toob 26" x 3.0"-4.8" PrestaTubeSurly Toob 26" x 3.0"-4.8" Tube for all Fat Bikes. This tube has a .8mm wall thickness to minimize the chance of getting a flat. This is a direct factory replacement for all Surly bikes and will also work with any bike using these wheel/tire dimensions. Removable Presta Valve Core.708752099739