This is a Magpul Industries Safety Selector known as the ESK, model MAG1071-BLK.
The Magpul ESK (Enhanced Selector Kit) offers a variety of selector levers for the Magpul SL Grip Module & HK Polymer Trigger Housings. Keeping with the Magpul blueprint of innovation" the Magpul ESK results in a modular" ambidextrous selector with enhanced ergonomics. With easier access to the user-configurable levers" the Magpul ESK allows firing hand activation and deactivation of the safety" while providing ambidextrous use. Constructed of high-strength polymer and corrosion-resistant steel" these components are built with the proven reliability Magpul is known for.
Features:
User-configurable levers for ambidextrous use
Easier firing hand access to selector levers
Constructed of high-strength polymer and corrosion-resistant steel components
Drop-in installation
Compatible with Magpul SL Grip Module & HK Polymer Trigger Housings
Compatible with three-position S-E-F and Safe-Semi trigger packs
