Bolts are fairly straightforward fasteners that consist of a head and threaded shaft. They are paired with a nut or inserted into a threaded hole to join together materials in order to facilitate a connection.

But what happens when two bolts need to be used in a tandem assembly? What are the options for extending a bolt’s threads in a different diameter or when metric and inch-based threads need to work together? Is there a way to use a metal bolt safely in an electrical setting? All of these things can be done with the addition of adaptors and other special bolt components.

Bolt extenders, threaded standoffs, and hex coupling nuts are examples of bolt adaptors. They allow for more complex connections and will solve problems in placements where an ordinary nut and bolt assembly will not work. They can also be used to join bolts with other fasteners, such as threaded rods.

The following bolt adaptors are some of the most common. This information will enable you to better understand their individual purposes and features so you can identify what you need.

Bolt Extenders

Bolt extenders can include many different types of bolt adaptors. They are also called extender sleeves. They feature a smooth exterior portion that is cylindrical with an interior hole that is threaded or female. This portion will accommodate the bolt. The end of a bolt extender has a threaded rod or male end, which is typically a smaller diameter and comes in varying lengths. Bolt extenders will heighten the clearance between the bolt and the installation surfaces.

Coupling Nuts

Also called bolt couplers or extension nuts, coupling nuts are tubes that usually have a hex-shaped exterior, enabling them to be turned with a wrench. The interior of the coupling nut is threaded so that two bolts can be attached at each end or threaded rods can be incorporated to extend the overall length of a fastener assembly. Coupling nuts make it possible to elongate connections with a simple addition. They are made in many different materials, but stainless steel coupling nuts, specifically 316 coupling nuts, are some of the most widely used because of their corrosion resistance.

Thread Adapters

Thread adaptors are very similar to bolt extenders. That can be used to pair metric and non-metric bolts and other fasteners that would otherwise be incompatible, such as USS and SAE or coarse and fine thread. They also provide options for pairing large diameter bolts with threaded holes that have a much smaller diameter or vice-versa. Through-hole thread adaptors can also allow bolts to fit with wider holes, enabling the shaft to pass through the connection. Thread adaptors also include female-ended thread adapters, which are similar to coupling nuts, and male-ended thread adapters, which accommodate two nuts.

Threaded Standoffs

Threaded standoffs are dual-ended fasteners that include a broad range of styles. They can be used to incorporate electrical insulation, 90-degree angles, and clearances that make it easy to perform regular sanitation practices, and account for other special situations where one or more bolts must be connected. Standoffs will also fit with nuts and other components. Standoffs also include hinged options that enable assemblies to be tilted by hand.