... 3.Closed-cell flexible 4.Fire proof, MoistureproofBellsafe-flex adopting NBR/PVC as the main raw material, is an environmental product.It ... rubber foam, fireproof apply in HVAC system Specification: Main material : NBR/PVC ID size:1/4", 3/8", 1/2", 5/8 ... 2mcompetitive price and high quality can beat any competitorPacking photo : NBR/PVC Insulation tube easy for installation