Carriage Bolt With Square Neck
What Bolt has a square neck?
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Carriage screws, also called rounded going settle neck screws, are square-necked threaded bolts commonly used in timber securing applications. The bolt’s settle neck prevents it from turning once installed using a nut.
Carriage bolts have a smooth, rounded head for a finished look. The square neck keeps these bolts from turning when tightening a nut.