This is a BLACKHAWK Cheek Piece known as the Adjustable, model 90CP01BK.
Add the Blackhawk Tactical Cheek Pad to your buttstock to aid in sight alignment and cheek weld. There are height-adjustable inserts and three adjustable straps with end retaining strap to prevent forward slip.
Features:
Non-slip material for positive cheek weld
Height-adjustable inserts
Three adjustable straps with end retaining strap to prevent forward slip
