The Z-Vent Gas Vent Systems from Z Flex install quickly and easily. The Z-Vent IV is a self-sealing Special Gas Vent System featuring air- and watertight connections to ensure optimum vent performance. The Z-Vent model SVE IV Special Gas Vent System is tested and listed to UL 1738 Venting Systems for Gas-Burning Appliances, Category II, III and IV. Features include gasketed connections, a high pressure rating, fusion-welded pipe seams and the ability to be cut to length in the field. Pipe is available in 6" to 10".Z-Flex.