5/8" x 1.312" OD Thru-Hardened Yellow Zinc Finish Steel SAE General Purpose Flat Washer / CROSS-SECTIONAL SHAPE STYLE: 1 RECTANGULAR HOLE DIAMETER: 0.649 INCHES MINIMUM AND 0.686 INCHES MAXIMUM PERIPHERAL SHAPE STYLE: 1 ROUND CENTER HOLE SHAPE STYLE: 1 ROUND THICKNESS: 0.074 INCHES MINIMUM AND 0.121 INCHES MAXIMUM OVERALL DIAMETER: 1.305 INCHES MINIMUM AND 1.342 INCHES MAXIMUM END ITEM IDENTIFICATION: 4320-01-617-7587 MATERIAL: STEEL OVERALL SURFACE TREATMENT: ZINC OVERALL