Designed in cooperation with Blitzkrieg Components the RB5020SS provides longer length and more weight for those who desire a short stroke competition action. With a length of 5.3”, this buffer will shorten the stroke of the bolt by 1.3” when installed in a standard AR15 carbine buffer tube. When installed in an AR10/A5 carbine buffer tube this buffer will shorten the stroke of the bolt by .5”, which can be increased by the addition of spacers. The damping level of this buffer is intended for lighter, competition type 9mm ammunition loadings for best performance and longest service life. * Using an AR-15 carbine buffer tube may require a modified bolt to properly reset the trigger.* Using an A5 buffer tube is recommended when using an unmodified bolt.    The RB5020SS can also be used with any PCC that uses an A1 or A2 rifle length fixed stock (internal depth 9.5″)