The slots are for the insertion of a cotter pin to secure the nut when used with a drilled shank fastener

Hot-Dip Galvanized material will meet or exceed ASTM A153 and/or ASTM F2329

1 L9 USS Tension Flatwasher Yellow Zinc Plated Domestic USA (20)

5 x 180 Hex Cap Screw 8

3/4-10 x 2 1/4 Hex Cap Screw SS 18-8 (A2)

7/8-9 x 10 1/2 A307A Hex Bolt Plain Steel 1 3/8-6 Socket Cap Screws Alloy The slots are for the7 8 9 x 10 1 2 A307A Hex Bolt Plain Steel. A307A Hex Bolts are manufactured from low carbon steel, typically 1015 1022. Our A307A bolting meets or exceeds ASTM A307 Grade A. Material is manufactured with rolled threads. Zinc plated material meets or exceeds ASTM F1941. Tensile strength will meet or exceed 60,000 psi.