... DuPont & Dow elastomers, neoprene, HNBR, NBR+PVC, natural rubber, SBR, IR, IIR(butyl rubber), CR (neoprene), SBR, AU, ACM, CO, etc. NSF ... -61 approved material, meet drinking water system. 2) All manufacturing processes ... ) Available in various sizes and colors Packing: 500pcs/bag Bathroom Rubber Fittings