Midwest Industries Same Plain Low Profile Rear Sight provides an extremely low profile dual aperture deisgn and features a locking detent with large surface area for maxiumum strength. The sight features the same ball detent battle proven design of the MI ERS Flip-Up Rear Sight that allows you to lock with stepped down turns to prvide a surface you can grab onto if you hands are muddy or wet. Featues: a Sits only .4375" when foldeda Locking detend with large surface area for maxiumum strengtha Same ball detent battle proven design of MI #: MCTAR-ERSa Lock detent button with stepped down turns provides a surface you can grab onto in adverse conditionsa Micro-style windage knob features the same MOA adjustments as the standard M16 (.65 MOA) & M4 (.49 MOA) a Made in the U.S.A.a MI LIfetime Warranty