The 1000 20 ga has, I think, a buffer under the gas piston. Got one from Numrich. So, having pulled and cleaned the piston, to get the action working, I am guessing the buffer sits inside the mag tube below the piston. Nothing anywhere on this, other than a mention that there is one. I suspect it may just sit on bottom of the piston bore, but not sure. Also, will it remain in place or use a dab of adhesive. My piston was gummed up and suspect it was the buffer....but just trying to do some homework before treading heavily. help appreciated