Model DH56 Recessed Quick Response, Extended Coverage Sprinkler For coverages up to 28 feet wide and 10 feet long(1). 250 psi (17,2 bar) rated. The Model DH56 family of sprinklers are quick response extended coverage sidewall sprinklers for use in light hazard applications. The Model DH56 with SWC cover plate is a concealed sprinkler that uses Reliable’s push on/thread off sidewall cover. This sprinklerhasthecupfactorymountedand is shipped with a protective cap that protects the 3mm frangible glass bulb during shipping and post installation finishing operations. The DH56 can be combined in the field with the FP or F2 Escutcheon to make a recessed sprinkler. TheSWCcover plate, FPand F2 recessed escutcheons have ½” adjustment. The SWC cover plate is attached with 135-degree solder. In the event of a fire the rising ambient temperature melts the solder and the cover plate is ejected away by springs exposing the3mmfrangible glass bulb. The use of a 3mm bulb allows quick response which enables the sprinkler to apply water to a fire sooner than standard response sprinklers of the same temperature rating.