Bulk SAE Flat Washers – Medium Carbon Thru-Hardened, Plain Finish, Made in USA – Monster Bolts Size:5000 Qty - 3/8" vibration-resistant internal threads—no tapping

vibration-resistant internal threads—no tapping

flush-mounted fastening

Attribute Specification Diameter 5/16" Thread Size 5/16"-24 UNF (Fine Thread) Drive Size 3/16" Hex Key Head Style Button Head Socket Cap Screw Material Alloy Steel – ASTM A574 (12

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Bulk SAE Flat Washers – Medium Carbon Thru-Hardened, Plain Finish, Made in USA – Monster Bolts Size:5000 Qty - 3/8" vibration-resistant internal threads—no tappingMonster Overview Fix your project right the first time with SAE Flat Washers Medium Carbon Thru Hardened, Plain Finish from Monster Bolts. These USA made SAE pattern washers feature a smaller outside diameter than USS washers and are ideal for machinery, automotive, equipment assembly, fabrication, and industrial applications. Manufactured from medium carbon thru hardened steel, these washers deliver a durable, consistent bearing surface under bolt