Yes, the only real picture of this obsolete timer found in MCI buses (motor coach international) used to program when the heater will start heating the engine coolant in order to pre warm up the engine during cold days.
Here is the manual related with this device. It was used with heaters model DBW 2010, DBW 2020 or DBW 300 Or newer version of the manual
699540.pdf Or newer version of the manual dbw2020.pdf
