VTech CS6209 Accessory Cordless Handset, Silver/Black | Requires a VTech CS6219 or CS6229 Expandable Phone System to Operate Digital security ensures your calls are digitized and encrypted, making it nearly impossible for someone to eavesdrop It is an accessory handset for CS6219 & CS6229 It has caller ID and call waiting features It has a handset speakerphone It has 50 name and number phonebook directory