Battle Arms Development Enhanced Pin Set (BAD-EPS) for the AR15 / M16 / M4 style rifles. The BAD-EPS features the following improvements and features: Precision Swiss CNC machined Available in OD Green and Flat Dark Earth AR15 / M16 / M4 Compatible - Fits all AR15/M16/M4 lower receivers with mil-spec .250in diameter front pivot and rear take-down pinholes. Patent Pending Pivot Pin & Takedown Pin Head Designs - Greatly improved gripping surface and pull strength without the use of oversize heads. Low Profile Pin Heads - Low drag and never in the way. Lower profile than mil-spec pinheads. Ambidextrous Safety Compatible - The Enhanced Takedown Pi Mfg: Battle Arms Development Inc.