A carriage bolt is a type of fastener that can be made from a number of different materials . A carriage bolt generally has a round head and a flat tip and is threaded along part of its shank. Carriage bolts are often referred to as plow bolts or coach bolts and are most commonly used in wood applications. The carriage bolt was devised for use through an iron strengthening plate on either side of a wooden beam, the squared part of the bolt fitting into a square hole in the ironwork. It is common to use a carriage bolt on bare timber, the square section giving enough grip to prevent rotation. The carriage bolt is used extensively in security applications, such as locks and hinges, where the bolt must be removable from one side only. The smooth, domed head and square nut below prevent the carriage bolt from being gripped and rotated from the insecure side. Sizes: Metric sizes range from M6-M20, inch sizes range from 1/4 '' to 1 ''. Package Type: carton or bag and pallet. Payment terms: T/T, L/C. Delivery Time: 30 days for one container. Trade Term: EXW, FOB, CIF, CFR.