| Black | Black Anodized Front Panel. Option 'P' is required. |
| Blue | Blue LED Displays |
| C | Crystal Time Base: A crystal reference is employed for those applications requiring independence from the line frequency. A trimming function is included for greater accuracy (2-3 seconds/week). |
| D | Remote Control: This option consists of a connector wired to switches on a control plate via a six-foot cable. Extra cable available. |
| ESE | ESE Time Code Output: An ESE Time Code output is provided allowing the unit to drive ESE Time Code Slaves. |
| Green | Green LED Displays |
| J | 220 VAC/50 Hz Operation: The unit is configured to operate from 220 VAC line voltage. 117 VAC 50/60 Hz is standard. |
| P | 19" Front Panel (Rack Mount): Designed for mounting into a standard equipment rack. Panel is 1/8" black anodized Aluminum and chassis is 5" - 10" deep. |
| Red | Red LED Displays |
| S | Parallel BCD Slave: Parallel BCD Slave for use with old style BCD Outputs. |
| T | Tenths of Seconds: Tenths of Seconds LED Display added. |
| UL | "UL" Approved Power Supply: The unit is supplied with a UL/CSA approved wall mount power supply. |