| A0 | North America |
| A1 | Universal European |
| A10 | China |
| A11 | India |
| A2 | United Kingdom |
| A3 | Australia |
| A5 | Switzerland |
| A6 | Japan |
| C3 | CALIBRATION SERVICE 3 YRS. |
| C5 | CALIBRATION SERVICE 5 YRS |
| D1 | Calibration Data Report |
| D3 | CALIBRATION DATA REPORT 3 YEARS (WITH OPTION C3) |
| D5 | CALIBRATION DATA REPORT 5 YEARS (WITH OPTION C5) |
| HS | High Stability Oven Oscillator |
| R5 | REPAIR SERVICE 5 YEARS (INCLUDING WARRANTY) |
| R5DW | REPAIR SERVICE COVERAGE 5 YEARS (INCLUDES PRODUCT WARRANTY PERIOD) 3 YEAR PERIOD STARTS AT TIME OF CUSTOMER INSTRUMENT PURCHASE |
| US | Ultra High Stability Oven Oscillator Time Base |