This is Eber model 70100003, almost identical to the current 70110003. It can switch an Airtronic D2, D4 or D5 on and off at set times over 7 days. It also regulates temperature. It does not include a temperature sensor or diagnostic capability. Dates from 2001 but in full working order.
Instruction book here.
Any offers around £50; I'll pay the postage or you can collect near Oban.
Derek