Abstract: In combination with a plurality of gas burning appliances and a gas source therefor, a gas distribution system having a main feed line connected at one end thereof to the gas source, a manifold feed means having a single inlet connected to another end of said main feed line and having a plurality of outlets, and a plurality of individual flexible feed lines each connected at one end thereof to each of the plurality of outlets of the manifold feed means, and connected at another end thereof to each inlet of the plurality of gas burning appliances. The individual feed lines are connected with at least one of the said burning appliances or the manifold means with a shutoff, quick disconnect coupling, which may have a fusible safety cutoff means including an element which responds to excessive heat to effect closing of a valve in said quick disconnect coupling to thereby block propagation of a flame wave through the coupling.