Permobond® RS-0545 Black Lead Cure Neoprene® (CR) Rubber. The lead content imparts better flame resistance, weather ability and ozone resistance than a typical CR rubber formulation. The permeation resistance of the mineral, vegetable, and animal oils is also better than all other CR linings. RS-0545 has good resistance to paraffinic and naphthenic oils of higher molecular weight but swell extensively in aromatic oils of low molecular weight. With the lead curing package and the addition of higher levels of filler loading we have improved the crosslink giving it exceptional resistance to oils, abrasion, and swelling in aqueous solutions and slurries.