The matte black Grand Slam Steel Top Mount Base #S25 from Weaver has been machined to tight tolerances for a custom fit. A square-cut notch mates to the sturdy cross bolt in every Weaver top mount ring.
Standard Front and Rear Base for:
Browning BLR (Lever Action)
Colt Coltsman in 223, 243, and 308 caliber (round receiver)