The AR-UL ACE Ultra Lite Stock, it is the lightest AR stock ever devised! Weighing only 5 oz., this stock uses Ace's original soft foam overtube for the ultimate cheek weld. A billet machined gusset reinforces the receiver extension tube at its weakest point directly behind the receiver. The aluminum butt plate also accepts an included 1/2" rubber butt pad you can add if desired. Installation requires A-2 buffer tube, rifle buffer, and rifle buffer spring. Mfg: Double Star