Wirsbo has obtained a patent on its combination plumbing/fire sprinkler system. The combination system features an interconnected grid of tubing that feeds both the sprinklers and the plumbing fixtures. The system has a stainless steel four-port fitting attached to the sprinkler head. Cold water manifolds feed the 1/2-in. AquapexR tubing directly to the four-port fittings. Remaining outlets on the fittings are used to feed other sprinkler heads or cold water plumbing fixtures.