This is a Battle Arms Development, Inc. Takedown Pins, model 100-013-491.
The Battle Arms Development Enhanced Pin Set features low-profile pin heads with greatly improved gripping surfaces. The design is compatible with an ambidextrous safety. Cone shaped recess at both pin tips prevent accidental bullet or tool slip and reduces the chance of scratching/damaging the receiver.
Features:
Ambidextrous Safety Compatible
Improved gripping surface
Extended Pin Tips