The Battle Arms Ambidextrous AR-15 Magazine Release Catch features a pivoting design to work with the standard magazine release button to provide true ambidextrous operation of the AR-15. FeaturesProcess: Investment cast (same process as Mil-Spec)Material: 8620 heat-treated steel Finish: Black Phosphate FinishConstruction: Two-piece design with a pivot pin and spring Design: Enlarged paddle for positive feel and offset from bolt catch to avoid accidental release. Skeletonized catch for weight saving. Does not pivot and mar the lower receiver wall.Compatibility: Will fit any AR15 style lower receiver that uses Mil-Spec magazine catch. Compatible with BAD-EMR (Enhanced Magazine Release), BAD-EMMR (Enhanced Modular Magazine Release), Mil-Spec Style Magazine Release, etc.Length: Shorter threaded pin to reduce installed magazine button height profile for solid face magazine release buttons