Battle Arms Development Enhanced AR Lower Parts Kit Black Phosphate. 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. Lightweight but Robust Design 0.39oz Compatible with Norgon Ambi-Catch Without Interference Raised "T-Shaped" Heel Provides Positive and Distinctive Control Surface for Bolt Lock Back Bold Horizontal and Diagonal Serrations Provides Positive Purchase Enhanced Single Sided Safety Selector (BAD-E4S-IC) for the AR15 Style Rifles. Based on our famous BAD-ASS Ambidextrous 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 made in specialized factories Enhanced Magazine Catch - BAD-EMC-IC 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) Specifications for Battle Arms Development Enhanced AR Lower Parts Kit: Manufacturer: Battle Arms Development Color: Black Finish: Black Phosphate Finish Fabric/Material: 8620 Heat Treated Steel Weight: 0.25 oz Condition: New Package Contents: Battle Arms Development Enhanced AR Lower Parts Kit Battle Arms Development BAD-LPK-PK3: Enhanced AR Lower Parts Kit Black Phosphate