TandemKross Accelerator Forward Thumb Ledge for Ruger Mark IV 22/45 helps improve grip and control. With a scalloped texture, you get the support you need for steady, firm grip. The additional point of contact safely, easily, and comfortably enables rapid and accurate consecutive shots on target. With easy, non-permanent installation, it's compatible with factory Ruger Mark IV 22/45 lowers and TANDEMKROSS's own Cthulhu Lower. Get your hands on this amazing upgrade for a reliable, comfortable grip and make your good gun GREAT today! FeaturesProvides stability and control for follow-on shotsEncourages proper gripSimple, non-permanent installation Compatible ModelsRuger Mark IV 22/45 (factory or Cthulhu Lower) NOTE: This accessory may prevent holster compatibility. Holster modification or a custom holster may be required for holster support.