Crafted from durable, corrosion resistant stainless steel, the Z-Vent® 4" Stainless Steel Single Wall Adjustable Pipe is designed for reliable performance in venting applications. The use of adjustable pipe may be required when the system must be located within extremely tight installation parameters. Adjustable pipe can only be used with adjacent pipe. Minimum 18" long adjacent pipe is required for full adjustment. The Z-Vent® double fail safe self-sealing gas vent system dramatically reduces installed vent system cost. It is designed for use with boilers, furnaces, spa heaters, pool heaters, unit heaters and water heaters.