Can be used as an individual, branch, circuit or stack vent;Fits 1-1/2" and 2" pipe sizes;Will vent up to 160 DFUs on a branch;Will vent up to 24 DFUs on stack;Expands architectural design limits;Reduces the number of fire-stopping applications;Exclusive vermin protection system;Limited lifetime warranty for replacement of defective valves;Residential or Commercial Use;ANSI/ASSE 1051, ANSI/ASSE 1050, NSF 14, ETL, ICC-ES PMG-1025, C-IAPMO