The Blast is a heavy duty 12 volt inflator/deflator with rubberized grip and is capable of inflating quickly and efficiently up to 1.5 psi. There are two ports on the pump - one where the air enters the pump and one where the air blows out. Simply disconnect the nozzle from the outlet side of the pump (it twists on and off) and connect it to the intake side.Notes:Never operate Blast with vehicle motor running - can overheat pump due to a higher volt output.Using this pump continuously for more than 20 minutes can cause it to overheat. Please allow cool down time between uses.