STP Seiko Seiki SCU-A1603C Turbomolecular Pump Controller Tested Working As-Is. Model No: STP CONTROL UNIT. It was tested in our facility and is working except the units digital display will not light up. Only items pictured are included: If a part is not pictured, or mentioned above, then it is not included in the sale. Pictured test equipment is not included or available for sale. For items with multiple quantities: The pictured item is not necessarily the one that will be sent. Serial numbers or country of manufacture may vary.