Feature:1. One Touch Answer Button: Wired telephone adopts one touch answer button, press it to answer or hang up the call.2. Volume Control: Wired telephone can use the cell phone volume control slider to adjust the listening volume.3. Sound Switch: The old school phone has an sound switch to further improve compatibility with different brands of smartphones. Works with most smartphones.4. 3.5mm Sound Plug: The wired telephone has a 3.5mm sound plug that is compatible with a wide range of smartphones on the market.5. Superior Performance: Wired telephone features retro styling; reduced cell phone radiation; superior sound quality; 9 feet coiled cord for added flexibility.Specification:Item Type: Retro Telephone ReceiverMaterial: ABSCompatibility: For All Smartphones and Computers with a 3.5mm Headphone JackFunction: Support Hang up and Answer.Package List:1 xRetro Telephone Receiver