Thread tunnel on dovetail with 1 1/4" (31mm), fits European match barrels with diameter 25mm (with adapters included .725" (18.415mm) and .812" (20.615mm))
Usable with M18/M22 front sight tunnel through optional front sight raiser
Vertical notched adjustments and reference scale
Designed for 520-35 (1.25") iris
Extremely robust clamping and design but lightweight