Rain Bird 212009 1" x 1-1/4" ACME Enlarging Outlet for Swing Joint Assembly - This ACME Enlarging Outlet is for use with the Rain Bird Swing Joint Assembly. Rain Bird Swing Joints are designed to deliver the performance you expect while saving you money with their superior flow characteristics and excellent structural integrity. Available in a wide range of configurations, Rain Bird Swing Joints are the perfect complement to our golf series rotors.