JP Enterprises Silent Capture System is a self-contained buffer system that reduces recoil, smooths out the operation of the rifle, and gets rid of the cheese grater sound of the buffer and spring. These are the best upgrades we have ever made to a rifle that you already own and a must if  in the process of building. Includes spacer to allow for installation in both carbine- and rifle-length buffer tubes. The H2 version is best suited for SBR's, running a suppressor, calibers that require an H2 buffer, select fire rifles and piston operated rifles.