The Little Gray Box Electric Water Heater Timer by Intermatic WH40 is a heavy-duty electric switch suitable for wall mounting. It features a rotary switch style with a single pole single throw (SPST) contact configuration, making it ideal for controlling electric water heaters. With a maximum amperage of 40A and a current rating of 31-40A, this timer is designed for efficient power management in any room. Additionally, the screw terminal electrical connection ensures reliable operation.