The Performance Tool W54151 Marine Lower Unit Adapter is an essential tool for any boater or marine enthusiast. Designed to fit most marine applications with its 3/8"-16 thread, this versatile adapter features a built-in swivel that allows for easy attachment to your water machinery. The included O-ring ensures a positive seal, preventing any leaks or spills during use. Made with durable materials, this adapter is built to withstand the harsh marine environment and last for years to come. With the Performance Tool W54151 Marine Lower Unit Adapter, you can ensure efficient performance of your water machinery, making it a must-have accessory for your next boating adventure.