The Curtis Instruments part 17305833 is a reliable and accurate solid-state digital hourmeter designed for use with both AC and DC power sources. It features a simple 2-wire installation and a non-resettable design, making it ideal for applications requiring long-term tracking of operating hours. The hourmeter has a 5mm non-backlit display, providing clear visibility in various lighting conditions. This model does not come with a logo and is compatible with power supply voltages ranging from 48 to 150VDC (nominal) and 36 to 185VDC (absolute), as well as 100 to 230VAC (nominal) and 75 to 270VAC (absolute).