Fernco P1006-66 6 Inch Flexible Coupling: Rubber Flex Fittings (018578001183-2)
Amazon.com: Taytools 6 to 4 Inches Flexible Hose Duct Reducer ABS Plastic with Designed to Fit Inside 4 inch and 6 inch Flexible Dust Collector Hoses 73473 : Tools & Home Improvement
PWHS - Z-Flex 2ZIKXXX0506 5 Inch Flexible Chimney Liner - 5 Inch x 6 Foot Gas Insul-Vent Double Wall Insulated Vent - Connector Kit
Master Flow 6 in. x 96 in. Aluminum Flex Pipe AF6X96 - The Home Depot
Fernco - 6 x 3″ PVC Flexible Pipe Coupling with Clamp - 82978776 - MSC Industrial Supply
Source 6 inch industrial hose joint piping braided flex pipe connector on m.alibaba.com
Zoro Select Flexible Coupling, For Pipe Size 6" x 3" 1056-63 | Zoro
Fernco 6-in Schedule 40 PVC Coupling in the PVC Pipe & Fittings department at Lowes.com
PVC, For 6 in Pipe, Flexible Coupling - 53UE48|DX1001-66 - Grainger