Push to connect reducers allow one to easily step down the original size of another push to connect fitting. Plug-in reducers are generally used on the push to connect ports on a manifold in the event that a smaller air line size must be used. An unequal union will allow you to reduce the air line size at any point throughout the system. If you have any questions about push to connect reducers, contact a Bag Riders air ride specialist for more information!