Connect and transfer torque between two shafts that are misaligned at an angle. Your shafts’ misalignment will affect the speed and torque these U-joints will be able to transmit. The more the shafts are misaligned, the less speed and torque they’ll be able to transmit.

Pin-and-block U-joints handle higher torque at lower speeds than other joint types such as those with needle bearings, making them a good choice for most applications. To extend their life by keeping lubricant in and contaminants out, use the grooves on their body to add a cover (sometimes called bellows or boots). Zinc U-joints are for hand-powered, low-speed applications. They are more corrosion resistant than steel U-joints.

U-joints for round shafts connect to shafts with spring pins (included with some U-joints). U-joints without spring pins require you to drill holes through both the U-joint and your shafts.