What he said.
But I wouldn't buy anything smaller than at least a 2HP for using air tools. I have a 3 HP sears unit, and it works just fine for all my needs (impact wrench, air ratchet, nail guns, ect). I had a 1.5 HP, and it did the job, but had a hard time keeping up when I was using an impact wrench alot. Had to stop and let it catch up once in awhile. But worked ok for an air ratchet and small nail gun.
So kinda depends on what you're needs are. But figure once you start using air tools, you'll see how great they are and start buying one of everything, then you'll wish you'd bought a bigger compressor(voice of experience here
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