256 Series - Dimcogray recessed top fluted knob
| Part N° | Material | Unit system | Fastening gender | A | B | C | D | Thread length | Thread size |
| 1-256-002 | Phenolic | Imperial | Female | 3-1/4 | 1-5/8 | 2 | 7/8 | 5/8 | 1/2-13 |
| 1-256-004 | Phenolic | Imperial | Female | 3-1/4 | 1-5/8 | 2 | 7/8 | 1 | 3/4 |
| 1-256-029 | Phenolic | Imperial | Female | 3-1/4 | 1-5/8 | 2 | 7/8 | 3/4 | 1/4 |
| 1-256-038 | Phenolic | Imperial | Female | 3-1/4 | 1-5/8 | 2 | 7/8 | 5/8 | 1/2 |
| 1-256-059 | Phenolic | Imperial | Female | 3-1/4 | 1-5/8 | 2 | 7/8 | 1 | 3/4 |
| 1-256-067 | Phenolic | Imperial | Female | 3-1/4 | 1-5/8 | 2 | 7/8 | 7/16 | 1/4-20 |