Model 963 with code B1C (Electronic air-processing unit, low) except code B1E (Electronic air-processing unit, high) Model 963 with code B1D (Electronic air-processing unit, medium) except code B1E (Electronic air-processing unit, high) Model 963 with code B1H (Electr. compressed air supply and control, centre) Model 964 with code B1C (Electronic air-processing unit, low) Model 964 with code B1D (Electronic air-processing unit, medium) Model 964 with code B1H (Electr. compressed air supply and control, cap4260w4381h