1/4 -20 x 3-1/2 Zinc Plated Grade 2 / A307 Steel Coarse Thread Carriage Bolts CBS-307

Diameter: 1/4 Length: 3-1/2 Material: Steel Finish: Zinc Head Style: Carriage Thread Size: 20 (Coarse) Thread Length: Full Hardness: Grade 2 / A307 Type: Carriage Bolt Square-Depth: 5/32 A carriage bolt has a domed or countersunk head and the shank is topped by a short square section under the head. The square section grips into the part being fixed (typically wood) preventing the bolt from turning when the nut is tightened.