This KX3 is threaded 5/8 x 24 to fit 300 aac blackout/7.62/.308 winchester. I got it for my 300blk, lubed it, mounted it, fired 10 rounds to check zero, and took it off, so it is used, but very lightly. It would be great on an SBR or pistol, but on my 16" it did not balance well. It did, however, do what it is supposed to, and significantly reduced blast and noise as perceived by the shooter. You will need a new crush washer, as "they" recommend using a new one with each installation. Price is $100 shipped.