Properties:

A circular item with two parallel bearing surfaces without hole(s) or groove(s). It has an outside diameter greater than its length, and may be fabric reinforced. Do not use if a more specific item name applies. For items primarily designed to rupture at a predetermined pressure, see disk, rupturable. For items made of felt, see felt, mechanical, preformed. For metallic or plastic items with a laminated cross section, see shim. Excludes diaphragm, valve, flat; diaphragm, valve, special shaped; disk, valve, nonmetallic; filtering disk fluid; and insulator, disk.