I keep getting pm from people on the thread pitch etc. For those that don't know this adapter goes from 12x1 to 1/2x28 this adapter is for those that are wanting to sbr their ps90 and use a muzzle device or silencer with common thread pitch. Any other questions pm me. Also I guessed on the price I don't know what one costs new I bought it along with abarrel service and did not ask for itemized receipt so feel free to make me an offer.