Zzzy criticality code justification, special clean for lox and ln service special features, cleaning, packaging, and marking iaw mil-std-1330d reference number differentiating characteristics

An item fabricated from nonmetallic material designed to be used where there is no relative motion between joined parts. Items with a solid cross section must be a single piece whose ends may have been secured together to form a specific shape. It may be formed to specific shape with or without joints. It may be a straight item of a specific length with end cuts or joints. It may have a solid or tubular cross section. Except for molded corners, end cuts, and mounting facilities such as mounting holes, slots, press-fit buttons, or the like, the item must be of one continuous round cross section. It may have fabric, cord or metal reinforcement. For straight items with square end cuts and without mounting holes, slots or press-fit buttons see rubber round section and tubing, nonmetallic. Excludes:gasket and packing, preformed.