Portable Inflator - press a button and within  30 seconds your tire will be inflated. Quick Tire inflation with automatic modes for preset PSI & automatic shutoff. Automatic altitude correction calibration, MAX 150 PSI. Long battery life with built in 7.4 V(2.5 Ah) Battery. Built in area for accessories such as Presta Valve, Needle & Charger cord. Compact, sleek design  8.25" x 3.5" x 2.75" Led Light  Will inflate at least 12 tires, 29" x 2" to 34 psi on 1 charge.