| CENTER HOLE SHAPE STYLE | ROUND |
| CROSS-SECTIONAL SHAPE STYLE | RECTANGULAR |
| HARDNESS RATING | 38.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM |
| HOLE DIAMETER | 0.331 INCHES MINIMUM AND 0.346 INCHES MAXIMUM |
| MATERIAL DOCUMENT AND CLASSIFICATION | ASTM F436 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| MATERIAL | STEEL OVERALL |
| OVERALL DIAMETER | 0.738 INCHES MINIMUM AND 0.768 INCHES MAXIMUM |
| PART NAME ASSIGNED BY CONTROLLING AGENCY | WASHER, HARDENED; COVER PLATE |
| PERIPHERAL SHAPE STYLE | ROUND |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | TT-C-490, TYPE 1 FED SPEC ALL TREATMENT RESPONSES OVERALL |
| SURFACE TREATMENT | |
| THICKNESS | 0.11 INCHES MINIMUM AND 0.13 INCHES MAXIMUM |