This emergency, break-glass operator is a separate component of the range of control and signaling units, Harmony 9001K diameter 30mm metal. It is compatible with Harmony 9001K push buttons. The operator is held in a depressed position by a glass disc, when the glass disc is broken with the hammer, button returns to a normal extended position. It weighs 150g. The 30 mm Harmony range offers a large choice of robust and reliable products to meet a great number of applications in heavy industries such as petrochemy, metallurgy, mining oil and gas wastewater treatment, automobile manufacturing. It is UL listed and CSA certified, CE declaration of conformity and RoHS compliant.