| B1 | OCXO reference oscillator aging: 2 x 10-7/year |
| DCV-1 | Documentation of calibration values |
| DCV-ZP | Printout of DCV (additional, in combination with DCV-Option only) |
| DKD | CTS/CBT DKD (ISO17025) calibration incl. ISO 9000 calibration (order only with device) |
| K4 | SW GPRS signaling for CTS30/55/65 |
| K7 | GSM module test for CTS30/55/65 before June'98 +CTS-U7 |