Towing a trailer with your vehicle is only safe and secure if you have a proper trailer coupling. Among trailer parts, the coupling might be one of the most important. A trailer doesn't trail if you cannot attach it to anything. If the coupling is wrong or damaged, the trailer may come apart and cause an accident. The couplings fall into four different types: fixed, brake-override, sway-control, and off-road, and each fits a certain kind of application.Fixed Coupling
The fixed coupling is the most common option, as it is also the easiest to use. Generally, it features a ball socket that goes over the vehicle's towball. The positive latch inside the socket locks against the towball's underside. A release lever on the coupling disengages the latch, so you can lift the coupling off if you need to remove the trailer. Fixed coupling is the perfect choice for trailers that weigh under 750 kg and do not require brakes. To prevent theft, you can also install a trailer lock.Brake-Override Coupling
The brake-override coupling activates the hydraulic or mechanical trailer brakes when a driver stops their tow vehicle. Brakes are legal requirements on trailers weighing more than 750 kg, so this type of coupling is suitable for such trailers. These couplings typically also feature a handbrake, so you can lock the brakes when you unhitch the trailer from the vehicle.Sway-Control Coupling
With a lack of load balance or strong crosswinds, the trailer might start swaying behind the tow vehicle. This is quite dangerous, especially when in traffic. Stabiliser or sway-control couplings help to reduce this sideward movement. The weight-distribution hitch, a complicated sway control method, features trailing arms that attach to the tow-bar tongue. These arms are under tension and can thus minimise sway. The other, more common option is the friction-type of hitch. This sway-control applies braking force to the towball, using friction pads inside the ball socket, reducing sway.Off-road Coupling
The off-road coupling offers the largest amount of roll and pitch, even 360 degrees compared to the 180 degrees of ordinary couplings. When driving on rough terrain, you need some flexibility in the form of rotation on several axles: the vertical, lateral, and longitudinal. These advanced couplings can include brake-override mechanisms as well, an essential option when using larger trailers.