I’ve used this pump a number of times & it works well, even in our Oklahoma heat. I haven’t tried using it off of vehicle battery power, yet, but it has worked very well off of internal battery power to inflate our two BOTE iSUPs and it recharges quickly using iPhone charger. It probably could inflate 2 or 3 more without recharging. One thing I choose to do is use the pump up to the first 4 to 6 psi and then manually pump to 12psi. The reason I do this is because the electric pump seems to put more pressure on the inlet valve causing it to slightly dislodge from its housing. At approximately 3psi the pump goes into high pressure mode & at 10psi the hose begins shaking and gets very warm, indicating hot air is entering the SUP. I suspect this puts undo stress on the glue used to secure the inlet valve housing. Regardless, this pump saves my back since manually pumping the remaining amount is nominal compared to pumping the whole thing.