This is a Mission First Tactical Grip known as the Engage, model EPGI16.
The Engage AR15/M16 pistol grip has interchangeable textured finger swells and back straps to provide a positive grip surface with wet or gloved hands and allow the user to customize the fit. A combination of fit and function unequaled by the original.
Features:
Black finish
Fits AR rifles pistol grip
Custom fit for any sized hand
Grip angle replicates M16 while not affecting trigger contact
Storage