| THREAD SERIES DESIGNATOR | UNC |
| NOMINAL THREAD DIAMETER | 0.164 INCHES |
| THREAD QUANTITY PER INCH | 32 |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.220 INCHES NOMINAL |
| FASTENER LENGTH | 0.220 INCHES NOMINAL |
| MATERIAL | STEEL COMP 410 PRIMARY WASHER |
| STEEL PROPERTY CLASS 18.8 FASTENER |
| SURFACE TREATMENT | PASSIVATE OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | ASTM A380 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| HARDNESS RATING | 40.0 ROCKWELL C MINIMUM AND |
| 50.0 ROCKWELL C MAXIMUM OVERALL |
| HEAD STYLE | PAN |
| HEAD DIAMETER | 0.306 INCHES MINIMUM AND |
| 0.322 INCHES MAXIMUM |
| HEAD HEIGHT | 0.105 INCHES MINIMUM AND |
| 0.115 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | CROSS RECESS TYPE 1 |
| WASHER QUANTITY | 1 |
| PRIMARY WASHER STYLE | FLAT INTERNAL TEETH |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.327 INCHES MINIMUM AND |
| 0.338 INCHES MAXIMUM |
| PRIMARY WASHER MATERIAL THICKNESS | 0.03 INCHES NOMINAL |
| FEATURES PROVIDED | LOCK WASHER |
| PART NAME ASSIGNED BY CONTROLLING AGENCY | NUM. 8 -32 X 1/4" PHILLIPS PAN HEAD GRADE 18-8 STAINLESS STEEL INTERNAL TOOTH WASHER SEMS SCREW |