Package included: 1 x Sprinkler Features: 1.Model:Y956 2.Material:Copper,metal alloy 3.Size:8.4*4.7*5.5cm 4.The product is consist of glass ball sprinkler,screw socket,outer cover 5.Compatible for fire sprinkler systems,good water spraying performance 6.Applicable for hotels, luxury restaurants, shopping malls, entertainment centers, etc.. Also can be installed in the crowded places, and warehouses and factories. 7.Hidden type sprinkler,more pratical Installation: The sprinkler and the screw sleeve seat is installed on the pipeline, and then install the outer cover. Outer cover seat and outer cover are welded into one by the fusible alloy. When the fire occurs,ambient temperature rises, achieve the fusible alloy melting point, outer cover fall off automatically, as temperatures continue to rise, the glass ball cover inside the sprinkler will be broken because of the sensitive temperature and liquid expansion, thereby sprinkler head open and automatically spraying water.