1/2"-13 x 4" Zinc Grade 5 Carriage Bolts (25 pcs.)

Diameter: 1/2"
Length: 4"
Material: Steel
Finish: Zinc
Head Style: Carriage
Thread Size: 13 (Coarse)
Thread Length: Full
Hardness: Grade 5
Type: Carriage Bolt
Square-Depth: 9/32"

Box of 25.

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.