Tacticon Armament's BattleGrip 4 Magazine Grip converts the well of your AR15, M4, or M16 into a comfortable vertical grip for increased control and stability.
Magazine Well Grip for AR15/ M16/ M4 FTF Industries Inc Firearms Parts & Accessories
FAB Defense Magazine Well Grip for M4/M16 Rifles (Color: Black), Accessories & Parts, External Parts, Vertical Grips and Hand Stops - Airsoft Superstore
AR-15® / M16 Swiss Pattern Vertical Fore Grip - Black Polymer - ProMag Industries
Mag Well Grips
FAB Defense OPMOD Ergonomic AR15/M16/M4 Pistol Grip
Mag Well Grips
Weapon Accessories
Grips For AR15, M4, M16, SR25, M110, And AR10 Rifles
Weapon Accessories
4965-(B)-CB : ERGO NEVER QUIT GRIP. Fits AR15/M16/M4 Magazine well - Coyote
MWG FAB Mag-Well Grip and Funnel for AR15/ M16 /M4 - ZFI-Inc
Mag Well Grips