The ARB was designed for shooters shooting from the prone position from a bipod. It is perfect for making that fine up/down or left/right adjustments needed to make that long shots. It can adjust 25 mm vertical and 18 mm horizontal and accept bags up to 150 mm wide and 210 mm long.
Specs:
Base width 210 mm
Base Length 300 mm
Base Leg width 330 mm
Weight : 4.1 kg