Since 2017, we’ve sold more than 15,000 AutoPlumb Water Neck Adapters with zero reported leaks. Our patented water neck adapters make it easy to convert a radiator, water pump, or thermostat housing to an AN cooling system without welding or permanently modifying your existing parts. The result is a clean, removable connection designed for custom cooling systems on LS swaps, muscle cars, street cars, race cars, and other custom builds. Whether you're building a complete AN cooling system or upgrading a single connection, our adapters are available in -16AN and -20AN to fit a wide range of applications. Shop AutoPlumb Water Neck Adapters at autoplumb.com #ANCoolingSystem #LSSwap #EngineBay #PerformanceCooling #ClassicCarBuild