Non-metallic flexible pipes, flexible tubes of plastic, flexible hoses, not of metal, non-metal hose fittings, valves of rubber or vulcanized fiber, and fittings, not of metal, for rigid pipes; waterproof sealants and expansion joint fillers; pipe gaskets; pipe couplings, namely, couplings of rubber for pipes; pipe jackets, not of metal; pipe linings, not of metal, namely, interior linings made of non-metal fabric and sealant for the repair of electrical, telecommunication and natural gas uti...