This is a Siemens 9T19 overload relay. It is a thermal overload relay designed for the protection of motors for overload, phase failure, and symmetrical current. It is designed for use in DOL (direct on line) starters. It has a 24 hr/7 day timer and and LED indicator. It can be used with devices up to 10 hp at 240V. It has a 1-phase operating coil, a rated operational voltage of 24V AC, and a rated operational frequency of 50/60Hz.