This extension hose is used with our 3' to 12' Expandable FlexiPort Power Tool Hose Kit (e.g. #68966 and also older style FlexiPort hose) to either double the length of your current hose, or to connect multiple tools at once with our 4'' to 2-1/2'' Y-Connector (#57072, sold separately). If you wish to splice hoses, the required coupler is included. If you wish to split hoses with a Y-connector, an additional 2-1/4'' swivel port is included to fit into the Y-connector. The same 2-1/4'' port will also fit most shop vacuums and dust separators. Additional hoses and Y-connectors can be purchased as needed to meet your needs. Of course, the kit may also be used to simply replace a damaged hose. The 3' to 12' ultra-flexible rubber hose is easy to maneuver and manipulate, is kink- and crush-resistant, and has no memory. Note: Couplers will only splice like hoses. The two FlexiPort hose systems—12' Fixed-Length and 3' to 12' Expandable—are NOT cross compatible.