The mod.104 is typical of those vents covered by international regulations with regard to emergency venting during fire conditions .

Four different executions are available :Aluminium model 104STD;Carbon steel 104EEV with stainless steel surface seat;Stainless steel 104VVV manufactured in AISI 304;
Stainless steel 104WWW manufactured in AISI 316;
Available in two sizes 20”and 24” with connections of any standard .Other sizes available upon request.
Settings range from +40  to +2000 mmWG . Counterweight device(type 104 CWD)  is equipped in order to get the high settings .