Anyone who has made the switch to a fixed mag solution knows that when you pull your take-down pin the upper receiver will drop and open your action all the way, costing you valuable seconds and possibly pinched fingers during a quick reload. The Cross Armory Flop Stop allows your upper receiver to open enough to drop your mag, but prevents it from opening more than necessary. In other words it keeps your receivers open at the perfect distance to drop your mag quickly, close your action, and get shooting again. The Flop Stop works in conjunction with the Cross Armory Pin Pal, which saves unnecessary wear on your receiver from frequent opening and closing. We are offering the Flop Stop in a bundle with the Pin Pal, or, for those who already own a Pin Pal, a standalone Flop Stop which easily attaches to your Pin Pal. The Flop Stop must be installed in a Pin Pal. Pair the Flop Stop with the Cross Armory Safe Mag and Quick Pins, and you will have the fastest fixed mag reload possible. However, Flop Stop is compatible with most other fixed mag solutions as well, such as the ARMaglock and Patriot Mag Release.
The Flop Stop is made from 4140 Ordnance Steel with melonite hard coat, and fits all AR-15 & M4 rifles.

Manufacturer Part Number: CRFS-PP ; CRFS