The optional offset inserts (not available for 30mm rings) allow a gun to be sighted in that cannot be zeroed with the available windage and elevation adjustments in the scope.
For serious shooters, the optional offset inserts allow a scope to be brought almost to complete zero, then using the windage and elevation adjustments only for the final, fine adjustment. This keeps the erector tube centered in the scope for improved scope clarity and performance.
Ring Diameter: 1"
Offset Insert Option: