LIGHTY USED Same plane low profile design, only .4375" when folded-A2 style dual aperture-made from 6061 aluminum, hard coat anodized-Locking detent with double the locking surface, for maximum strength-Same ball detent battle proven design as the MCTARERS Flip Up Rear Sight-Lock detent button with stepped down turns, easy to grab even with muddy or wet hands-Same style windage knob as on the standard M-16: .65 MOA on M4 type rifles/.49 MOA on A4 type rifles-