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). Ball-and-socket U-joints rotate in any direction, just like your shoulder. They have an oil reservoir that holds lubricant and feeds it slowly to the ball and socket.

Steel U-joints are strong and handle more torque than zinc U-joints. Zinc U-joints are for hand-powered, low-speed applications. They are more corrosion resistant than steel U-joints.

U-joints for keyed shafts connect to shafts with set screws. Unlike U-joints that use spring pins, there’s no drilling required. 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. U-joints with spring pins already have holes, so you only need to drill holes through your shafts.

For technical drawings and 3-D models, click on a part number.