AIM Sports AR/AR15 Low Profile Front & Rear Flip-Up Sight/V2 Free Shipping & Limited Lifetime Warranty Quick detachable with adjustable A2 square post. A2 style dual aperture Automatically locks into position when raised. Flip-up posi-lock design to guarantee zero Rear Sight: 0.65 MOA on M-4 Type rifles. 0.49 MOA on A-4 type rifle. Length: 2.5" Front Sight: ame plane hand guard / upper receiver height. Length: 2.3"