The JP Enterprises GEN 2 Silent Captured Spring eliminates the loud noise of the standard M4 buffer spring and is designed with a perfect centerless-ground spring and precision polished outside diameter. This allows your BCG (bolt carrier group) to reciprocate inside the buffer tube faster, smoother, and more reliably. The single piece design makes it easy to remove from the buffer tube for cleaning, maintenance, and custom tuning. The weight of the buffer can be increased or decreased to match the needs of your rifle depending on the type of ammo being used or if a suppressor is being used. The silent capture spring also includes a spacer to make it compatible with both carbine and rifle length buffer tubes.