Schneider Electric ZB4BC3 Mushroom push button head Ø40, metal, green, Ø22, spring return. This Harmony XB4, 40mm mushroom green button head operates with a spring return mechanism. This 40mm mushroom shaped push button head is ideal for situations where quick actions are required for a process or machine to function correctly or where operator movements require maximum ergonomy. It is easily combined with Harmony range of contact blocks to perform a large variety of control functions. It is clearly distinguishable visually at a distance thanks to a prominent 40mm mushroom shape. It is impact resistant, dust resistant, water resistant and vibration resistant thanks to its IP66 / IP67 / IP69 / IP69K. It has a metal bezel, this makes it Ideal for applications requiring high impact and vibration resistance. It is designed to fit in a standard 22mm cutout, ensuring compatibility when installing in pre-existing machinery. Its wide range of operating temperatures from -40°C to 70°C allows versatility in usage of product. Official Schneider characteristics include Range of product: Harmony XB4; Product or component type: Head for non-illuminated push-button; Device short name: ZB4; Bezel material: Chromium plated metal; Mounting diameter: 22 mm; Sale per indivisible quantity: 1; Head type: Standard; Shape of signaling unit head: Round. Harmony XB4 devices use a chromium-plated metal bezel and are designed for robust panel operation where clear manual control, indication or machine safety interfaces are required.