Crosstac AICS/V-22 Maintenance Block - Adjusts to fit snugly in the 22LR AICS magwell with multiple nylon set screws. Two angles are milled into the base of the block. Designed to clear bolt raceway for trigger tuning work. Durable HDPE Plastic CNC Precision Machined Three Side Adjustment Nylon Set Screws, One Front 10 Degree Down Angle For Solvent Control Clears Bolt For Trigger Tuning Holds Rifle Stable For Any Work Made In The USA