AR15 M16 Front and Rear Flip up 45 Degree Rapid Transition Backup Iron Sight Combo for Picatinny/Weaver Rail Mount QD Automatic 45 Degree Flip Up Deploy Button Release At The Push Of A Finger And Locks In Place When Deployed Or Folded. Mounting Decks designed to be used with handguard & Flattop rails and both will fit all 7/8" Picatinny/Weaver style rails. Easy Quick And Secure Installation -Allen Screw Locking Clamp Rail Base Retention For Maintaning Zero Under Heavy Conditions. Dual Aiming Apertures where you can either use pin dot sight or full bore sight Made of 6061 Aircraft Aluminum and T6 Heat treated Aluminum body