Battle Arms Development has put together an Enhanced Complete Lower Parts Kit! The Battle Arms Development Enhanced Complete Lower Parts Kit consists of Battle Arms high quality parts you already know and love, with the added bonus of several Investment Cast items, to ensure the most robust parts for your build. Enhanced Bolt Catch, which is a cost friendly alternative, without sacrificing the quality for your AR build! The AR-15 Cast Enhanced Bolt Catch is 8620 heat treated cast steel with a manganese phosphate black finish. With this upgrade you have a versatile modular design, enhanced control surfaces, lightweight engineering, and better ergonomics. Enhanced Single Sided Safety Selector for the AR15 Style Rifles- based on the famous BAD-ASS Ambidxtrous Safety Selector with distinctive and diagonal serrations Single Side Safety Selector (0°-90° SEMI AUTO) Fit all Mil-Spec Dimensioned AR-15 Lower Receiver Black Phosphate Finish Investment Cast 8620 Heat Treated Steel Enhanced Magazine Catch Process: Investment Cast (Same Process as Mil-Spec) Material: 8620 Heat Treated Steel Finish: Black Phosphate Finish Construction: One Piece Engineering (Not Two-Piece) Design: Lightweight Fluted Design Compatibility: Compatible with Mil-Spec Magazine Release Button, BAD-EMR, BAD-EMMR, etc. Length: Shorter Threaded Pin to Reduce Installed Magazine Button Profile of Solid Face Magazine Release Buttons Weight: 0.25 oz (v.s. 0.32 oz Mil-Spec) BAD-EMR (Enhanced Magazine Release) for the AR15/AR10. Precision CNC Machined for billet 7075-T6 Aluminum (not 6061) in an anodized BLACK finish, the BAD-EMR features an unique, fully solid "V" shaped button face with horizontal serrations (no thru hole). The concave V-Groove button face offers excellent ergonomic feel and self-centers the index finger as pressure is applied. The horizontal, parallel serrations helps slippage in the vertical orientation while minimizing drag in the horizontal direction for finger retraction. The BAD-EMR also features a lightweight skeletonize back to offset the weight gained from the fully solid button face and slightly increased height to equal the weight of the standard mil-spec magazine release (approxmiately 0.002 lbs). BAD-EMR is compatible with all lower receivers that accepts mil-spec magazine release buttons. BAD-ATG™ Adjustable Tactical Grip easily adjusts, with the included hex key, to each of the three most popular industry proven angles (17, 25, & 33 degrees) using the Patent Pending adjustable angle mechanism. The textured finger grooves and ribbed back-strap optimize comfort and provides positive control. Dimpled air gaps help keep hand dry while offering firm grip texture. Only 3.0oz complete with screw and washer! BAD-EPS Takedown and Pivot Pins: AR15 / M16 / M4 Compatible - Fits all AR15/M16/M4 lower receivers with mil-spec .250" diameter front pivot and rear takedown pin holes. 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 pin heads. Ambidextrous Safety Compatible - The Enhanced Takedown Pin (BAD-ETP) head design does not obstruct the use of the right side ambi safety selector lever. Extended Pin Tips (+0.030" over milspec) - Added tip length noticeably aids in starting/pushing the pins out from the left side of the receiver, without undue protrusion. Each BAD-EPS comes with (1) BAD-ETP, (1) BAD-EPP, (2) KNS hardened stainless steel detents, (2) 17-7 nickel plated stainless steel pin springs, and (1) high-strength neodymium magnet for hassle free magnet assisted installation of the Enhanced Pivot Pin (BAD-EPP). Mil-Spec Trigger And Hammer Nickel Teflon Semi Auto Hammer and Trigger Disconnector Disconnector Spring Hammer Spring Trigger Spring Springs and Detents Qty 2 Takedown / Pivot Pin Springs Qty 2 Takedown / Pivot Pin Detents Qty 1 Bolt Catch Detent Qty 1 Bolt Catch Spring Qty 1 Trigger Guard Qty 1 Trigger Guard Roll Pin Qty 2 Hammer / Trigger Pins Mil Spec Qty 1 Safety Selector Detent Qty 1 Safety Selector Detent Spring Qty 1 Magazine Catch Spring Qty 1 Buffer Retainer Detent Qty 1 Buffer Retainer Detent Spring