The King combination belt/disc sander takes a 4×36“ belt and 6” adhesive backed discs. Please use dust collection with this tool. When changing the belt, be sure to orient the belt the right way to avoid ruining the splice. Flick the switch on and immediately off. Adjust the tracking Knob if it's not running straight. When changing the disc, you may need to clean the residue off the old disc with acetone. Don't put a new disc on if the surface isn't clean. You'll waste a disc.