Topeak JoeBlow Dualie Floor PumpDesigned for low pressure Fat Bike tires and moderate pressure MTB tires. A massive over sized barrel is 1. 5 times larger than a standard floor pump and delivers large air volume to fill over sized tires quickly. 0 30 psi gauge for fat tires, 0 75 psi for Mtn tires Air release button on Twin Head allows to fine tune exact pressure Works on Schrader, Presta and Dunlop valves 44. 4mm Steel Barrel with composite base and handle Dimensions: 27. 2 x 9. 1