| Model Code | Description | |
|---|---|---|
| 01 | 309.000, 309.001, 309.011, 309.012, 309.013, 309.014, 309.015, 309.016 | SINGLE-CIRCUIT BRAKE |
| 02 | 309.002, 309.003, 309.024, 309.025, 309.026 | SINGLE-CIRCUIT BRAKE |
| 03 | 309.070, 309.071, 309.072, 309.073, 309.090 | TWO-CIRCUIT BRAKE |
| 04 | 309.083, 309.091 | TWO-CIRCUIT BRAKE |