This will increase precision and zero repeatability during disassembly and reassembly when accomplishing maintenance. Set up was straightforward and easy, outstanding design. Only needed to use one particular shim to acquire it at 11’oclock, excellent fit and small if no hole. After about 6 months or so of use now https://manuelgrboy.ka-blogs.com/79781516/5-simple-statements-about-knights-armament-m4-quad-rail-explained