TandemKross Accelerator Thumb Ledge Features The TandemKross Accelerator Thumb Ledge mounts to any pistol with a 1913 Picatinny or Weaver rail positioned under the barrel making installation straightforward and fully reversible with no permanent changes to the host firearm. Adding this extra point of contact gives the shooter a more stable and repeatable grip particularly useful during rapid-fire strings or precision target work where hand position consistency matters. The thumb ledge is built from durable lightweight aluminum keeping the added weight on the pistol to a minimum while still providing a rigid mounting point. This design lets shooters fine-tune their grip without altering the factory configuration of their firearm. This particular model is configured specifically for left-handed shooters positioning the ledge for a natural ergonomic thumb placement on that side of the grip. It is designed to fit the Ruger Mark IV 22/45 a popular rimfire pistol platform among competitive and recreational shooters alike. The black finish keeps the accessory low-profile and visually consistent with most Mark IV configurations. For left-handed Ruger Mark IV 22/45 owners looking to add a stable no-modification thumb rest the TandemKross Accelerator delivers a simple and effective upgrade. TANDEMKROSS Accelerator Thumb Ledge Specifications Manufacturer: TANDEMKROSS Model: Accelerator Thumb Ledge Compatible Hosts: Ruger Mark IV 22/45 Material: Aluminum Color: Black Handedness: Left Hand Available At: GrabAGun