VTech CS6609 Accessory Cordless Handset, Silver/Black | Requires a VTech CS6619, CS6629, CS6648, or CS6649 Expandable Phone System to Operate DECT 6.0 Digital technology NOTE: Accessory handset onlyrequires a CS6619, CS6629, CS6648 or CS6649 series phone to operate Caller ID/Call Waiting*stores 50 calls Handset speakerphone Quiet Mode DSL Subscribers may need to us a DSL Filter;Trilingual prompts allow you to choose between English, Spanish and French For optimal performance batteries should be charged for 16 hours prior to use. NOTE: Kindly refer the User Manual and the Guide from the Technical Specification before use which is highly recommended.