Here is what IK Multimedia say about the iRig Pads Being smaller than an iPad and less than 1' thick means that it you can put it in nearly any laptop or iPad bag and carry it with you without a power supply from gig to gig thanks to the bus power supply that can even run off of an iPad.

One of the great points of this product is just how portable it is. Sometimes you need more options than what are available to you on one scene so with the iRig Pads you have total recall with 16 user-programmable scenes that you can bring back any time you want so you don't have to change your settings between each section or track. You also have 2 MIDI knobs, one slider and a pushbutton rotary encoder which are all completely programable to whatever software you want to use. With 16 velocity sensitive pads with 3 colour lighting under each one the iRig Pads not only sends your playing into your software of choice but also feeds back that information so you can quickly adjust and see exactly what is going on with each pad in your set up. The iRig Pads opens up the world of midi triggers for DJ's and live producers through an iOS device though it also works with PC and Mac computers.

Sampletank 4 se sounds