Amazon.com: PATIKIL ID 50mm/2" OD 45mm/1.8" Pipe Fittings, 2 Pack Splitter Duct Hose PVC Connector for Drain Tubes, Drip Systems, White : Industrial & Scientific
HVAC OV Eccentric Plastic Duct Connector for 4" inch to 5" inch Pipe Fittings. Adapter for Inline Heating and Cooling Vent ducting. Soft and Straight Pipe Connection. - Amazon.com