I bought this several years ago direct from STAG arms. I have another one on my Stag Ar, and it works great. I mounted this to another gun, which I am selling, so I don't need it.
It only has 100 rounds or so through it.
Stag said these were especially effective on full auto rifles. I don't think they offer them anymore, but it really works great on semi auto.
This is for 223/556 rifles with standard AR threads. Comes with the crush washer. This has three large ports up, and a ring of small ports around it's circumference. no large ports down-facing.
prefer PP no extra fees!! USPS mo OK. Personal checks need 12 days to clear.