Aimsports ar-15/m4 flip up rear sight feature dual aperture for long and short range, ball bearing pivot detent, automatically locks into position when raised, flip-up posi-lock design to guarantee zero and a2 style dual aperture.0.65 moa on m-4 type riflesand 0.49 moa on a-4 type rifles.Rear Color: Black AnodizedType: Flip Up Front/RearFrame Material: AluminumFrame Color: Black AnodizedFirearm Fit: AR-15, M4Style: FoldingFront Material: AluminumRear Material: AluminumFront Color: BlackFirearm Type: AR-Platform