Also called the Receiver Extension, this quality part is machined to commercial specs from an aircraft aluminum extrusion to accept the6-position adjustable telestock. Precision notches on the underside offer 6 positions for setting length of-pull. If you’re swapping over from a rifle length stock or replacing a worn buffer tube, this is what you need (along with the appropriate carbine buffer and CAR action spring). Finish is hardcoat anodized, and dry film lube coated inside for smooth operation of the buffer and buffer spring. Made in the USA to provide excellent fit and reliable function in your AR15/M16.