These 4pc flash hiders have 24x1.5RH threads, They fit the AR-M1 . AR-M9F . SAM7SF . AR-M4 SF . SAM7K . SAM7R . SLR-101 . SAM5 and others. I've been waiting to get them into the USA because they are so hard to get past customs. But I have a few that I'm selling for much less than kvar US made crap. I take discreet Friends and family PayPal or postal money order can also accept bank check. These are $240 shipped which is less than kvar sells for 300 plus 13 shipping so don't pay for what they claim they have! $240 shipped first come first served. This is the absolute best price Anywhere!!! These won't last long, no haggling no discounts just a really good deal. If you have claimed parts I sell before and disappeared then don't bother with asking for one of these. Sorry but I've had a bunch of tire kickers lately.