Enhance your firearm's performance with the JP Silent Captured Spring System designed specifically for seamless integration with the Maxim Defense CQB Stock System. Crafted from durable tungsten and stainless steel this heavy-duty spring system ensures smooth and reliable operation. Its unique design requires an open channel in the bolt carrier group allowing the guide rod to function flawlessly during firing. Finished in an elegant silver this model combines robustness with sleek aesthetics providing a superior shooting experience.