We do not recommend the Vortex Hunter Rings for use on heavy recoil rifles. They are economical 1-inch rings that accept mounting to a Picatinny or Weaver rail. The standard 2-screw Vortex Hunter one inch rings are a good match for general hunting setups. Made from aircraft-grade 6061-T6 aluminum for optimum strength. Available in three heights (Low, Medium or High) for 1 inch riflescope tubes.