Carry handle sight installation - XTS AR Carry Handle Rear Sight

I have bought 2 different Carry Handle rear sights from 2 different suppliers and different brands they are not something you take out of th box mount in place and go ans zero them and shoot. I have had to fit them to the rifle in both cases. This last one the front screw was mounted crooked I had to file it flat as it was bottoming out in the slot of the top rail and not allowing it to sit down flush on the rail. The front mounting point was also not straight and I had to use needle files to straighten it and lower the edge so it would grip over the edge of the rail to be held down enough to be held on. I personnaly use this sight because it is what I am used to 22 years Army, they are quick and easy to get on target and with practice very effective even out to 450 meters. However, if you but one you need a needle file set, a fine small flat file, a new green scotch brite pad,( sometimes you need to buff down the finish on the top rail of a new rifle and the inside mounting surface of the sight) and a tube of lock-tite to go on the mounting edges and hold down screws to hold the sight in place after you have fitted it several times and got every thing flush and located correctly. If you don't want to do all this buy a more expensive name sight.