Extra High See-Thru Rings & Bases Designed to fit CVA Apollo 90, Modern Muzzleloader Knight & MK-85,Traditions White Tail & Buck Skinner & Thompson Center Hawken & Renegade and other Flat Receivers. with 8-40 or 6-48 hole size…. SEE-THRU MOUNTS ARE DESIGNED FOR MAXIMUM VIEWING AREA FOR HUNTING IN ALL KINDS OF WEATHER AND NEVER LOSE THAT IMPORTANT SHOT   In Bright Black, Matt Black or Stainless Finish