These direct thread adapters are made by Rearden MFG and are a second generation to the ZR0 DTA. The wrench flats in the rear were extended by .125 for a place to get a wrench on if needed. The inside was also opened up to give more internal volume making this gen 2 LIGHTER than the gen 1 by shaving off an extra 0.3 oz. Made to work with industry standard 1.37524 threaded suppressors the ZR0 DTA was made to add as little length to the system as possible while being as light as possible. Made from 6Al-4V grade 5 titanium with a PVD coating the ZR0 DTA comes in at 0.9 OZ. If inches and ounces matter to you and you're a fan of direct thread mounting then you will find no better mount than the ZR0 DTA.