This True Precision recoil spring tuning kit is built for the Ruger RXM and aftermarket copies. Six spring weights let you tune cycling for a compensated or suppressed RXM, a lighter or heavier slide, or a change in ammo. The springs are high-strength chrome silicon, rated for more than 20,000 compressions each. The kit includes a billet-machined stainless steel guide rod (non-captured), so you can swap spring weights without buying a new rod assembly. Features: Designed for the Ruger RXM and aftermarket copies High-strength chrome-silicon springs Stainless steel, billet-machined non-captured guide rod Includes 11 lb, 13 lb, 15 lb, 18 lb, 20 lb and 22 lb springs 100% made in the USA Start with the spring weight closest to your current setup and adjust in one step at a time. Function-check with your carry ammo after each change, and confirm reliable lock-back on an empty magazine before you carry or compete with it.