Flat head carriage bolts are a type of fastener commonly used in woodworking and construction projects. They are named for their distinctive flat, smooth head, which provides a flush finish when installed. These bolts are designed to be used with a corresponding square or rectangular hole in the material being fastened.

The flat head carriage bolt consists of a threaded shank and a flat, countersunk head. The shank is typically square or rectangular in shape, preventing it from rotating when tightened with a wrench or pliers. This design feature makes them ideal for applications where a strong, secure connection is required.

Carriage bolts are often used in situations where the bolt head needs to be flush with the surface or where a decorative finish is desired. The flat head design allows for a clean and neat appearance, making them suitable for visible applications such as furniture assembly, cabinetry, and architectural projects.

One of the key advantages of flat head carriage bolts is their ease of installation. The square or rectangular shank prevents the bolt from spinning in the hole, making it easier to tighten the nut without needing to hold the bolt in place. This feature is particularly useful when working in tight spaces or when using power tools for installation.

Flat head carriage bolts are available in various sizes, materials, and finishes to suit different applications. Common materials include steel, stainless steel, and brass, each offering different levels of strength and corrosion resistance. The choice of material depends on the specific requirements of the project, such as load-bearing capacity or exposure to moisture or chemicals.

Flat head carriage bolts are versatile fasteners that provide a secure and flush connection in woodworking and construction projects. Their flat head design allows for a neat and finished appearance, making them suitable for visible applications. With their ease of installation and availability in different sizes and materials, flat head carriage bolts are a popular choice for many professionals and DIY enthusiasts.