The Intermatic T101D89 24 Hour Mechanical Timer Wall Switch is a durable and heavy-duty electrical switch suitable for both interior and exterior walls. With a rotary dial control style and a switch operation method, this timer switch allows for convenient scheduling and automation of your electrical devices. Featuring features such as vacation mode, auto-off, and a dusk-to-dawn cycle, this timer switch is designed for energy efficiency and peace of mind. The switch is illuminated and includes an indicator light, making it easy to use and monitor. Additionally, the switch is tamper resistant and includes a cover for added security.