280 Series - Dimcogray recessed top knurled knob
| Part N° | Material | Unit system | Fastening gender | A | B | C | D | Thread length | Thread size |
| 1-280-007 | Phenolic | Imperial | Female | 1 | 39/64 | 5/8 | 5/16 | 3/8 | 5/16-18 |
| 1-280-020 | Phenolic | Imperial | Female | 1 | 39/64 | 5/8 | 5/16 | 5/16 | 1/4 |
| 1-280-031 | Phenolic | Imperial | Female | 1 | 39/64 | 5/8 | 5/16 | 5/16 | 10-24 |
| 1-280-037 | Phenolic | Imperial | Female | 1 | 39/64 | 5/8 | 5/16 | 5/16 | 3/16 |
| 1-280-600 | Phenolic | Metric | Female | 1 | 39/64 | 5/8 | 5/16 | 7.9 | M5-.8 |