SNSL male couplings with EPDM gaskets enable making flexible connections. They can be used as expansion joints in ductwork or for connecting ducts at floor penetrations. SNSL male couplings can also be installed for splicing replaced ducts in legacy systems. It is a popular solution for ventilation ducts continuously exposed to temperature variations which affect thermal expansion and shrinking of the ductwork. The fitting is also perfect for connecting fire dampers to the ductwork.