MGRIP1: ERGONOMIC CQB GRIP w/ Battery Storage & Pressure Switch Mount - Finger grooves for increased control especially under adverse conditions - Captive thumbnut can't be lost. Provides quick and easy installation without tools to Picatinny rail - Finned design reduces weight and dissipates heat. - Two removable pressure switch mounting covers - Securely attaches to any Picatinny rail - Plugged cap provides waterproof battery storage - Side rails assist in guiding magazine into well - Fits: Picatinny Rail - Made of: Polymer - Weight: 2.56 oz - Length: 3.5 - Height: 3.5 - Width: 1.6