A plow bolt has a flat or countersunk head to allow for a smooth finished surface. Similar to a carriage bolt there is some type of locking base directly under the plow bolt head, most commonly a square base. This keeps the bolt from turning once tightened. The base under the head needs to match the surface the bolt is mated with. The most common use is on plow blades and heavy construction equipment.
Available in UNC 3/8″, 7/16″, 1/2″,9/16, 5/8″, 3/4″, 7/8, 1″, 1-1/4″ threads in a range of lengths.