GUESS WHO MAKES THESE... DONT KNOCK THEM THESE WORK.THE TRICK IS IN THE FITTING ON YOUR WEAPON.. THEY FIT BOTH METRIC AND INCH RECEIVERS, MADE OF AIRCRAFT GRADE ALUMINUM ALLOY,MAINTAINS THE USE OF IRON SIGHTS,ALSO WORKS ON AFTER MARKET STANAG SCOPES AND ORIGIONAL SCOPES.AS WITH ALL OF THE SCOPE MOUNTS OUT THERE FOR FALS EXPENSIVE AND NOT THEY ALL REQUIRE A LITTLE FITTING, MY DSA MOUNT NEEDED TO BE FITTED... JUST DONT USE A POWER TOOL....IT A 2 BEER JOB!!!... ALSO USE SOME TYPE OF lite THREAD LOCKING STUFF ON THE WEAVER ADAPTOR SCREWS AND THE MOUNTING SCREWS.