Rubber bushing for synthesizers which use the Pratt-Read keyboard assemblies (many of the classic Moog, Arp, and other synthesizers used these). Replacing the hardened and brittle bushings in an old synth will restore the key action to feeling brand new! If some keys are sitting higher than others, replacing the old bushings (and bending the mounting tabs if necessary) will even out the keys. These bushings should be installed in the orientation shown in the lower photo, and should be lubricated before the keys are reinstalled; the recommended lubricant is Dow Corning 7 Release Compound (a silicone grease).
This part is NEW.