16 Inch 18 Inch 15 Inch 14 X 34 Cross Countersunk Carriage Bolt Din 603 Flat Head Metal

 high precision good quality waterproof flat head metal 14 x 34 cross countersunk head screw for computer case fan

carriage bolt, also known as a coach bolt or round head square neck bolt, is a type of threaded fastener with a distinctive domed head and a square or rectangular shoulder section just below the head. Carriage bolts are typically used to fasten wood or metal components together. Here is a description of a carriage bolt:

1. Construction: Carriage bolts are usually made of steel, stainless steel, or other alloy materials. They consist of three main parts: a round, domed head with a smooth, slightly curved top surface; a threaded shank that extends from the head; and a square or rectangular shoulder section located directly below the head.

2. Head Design: The domed head of a carriage bolt is typically larger in diameter than the threaded shank. It provides a smooth, finished appearance and offers a bearing surface when installed. The top surface of the head is usually flat or slightly rounded, making it suitable for applications where a flush or low-profile finish is desired.

3. Square Neck: One distinctive feature of a carriage bolt is the square or rectangular neck section just below the head. The square neck is designed to fit into a corresponding square hole or slot in the material being fastened, preventing the bolt from rotating during installation. This feature allows for easy one-person installation, as the bolt can be held in place while the nut is tightened on the threaded end.