This is a Ergo Grip Rubber known as the Sure Grip, model 4055BK.
The ERGO AR15/M16 Tactical Deluxe Suregrip with Palm Shelf is an ergonomically enhanced pistol grip that fits all AR/M4. The ERGO tactical deluxe is an ambidextrous pistol grip that features the SUREGRIP texture and a Palm Shelf for increased stability. It's wider" heavier textured design makes for better handling and the A2 sized inner cavity is capable of storing many kit systems.
Features:
Fits AR-15 type firearms in .223 and .308
Over molded SUREGRIP material with heavy texture
Adjustable palm shelf
Fits medium to large hands best
