Ultra-rigid vertically split rings use oversize hardware for extra strength and ease of installation. For mounting on Browning Weaver-style two- or one-piece style bases. Compatible with the two-piece scope bases for A-Bolt, BAR, BLR and the X-Lock. Intermediate (.400"), for scopes with an objective up to 50mm and a standard barrel contour. High (.500"), for scopes with an objective up to 56mm and a standard barrel contour.