A:AnswerLiza - The compatible accessory cordless handset of the VTech CS5329 is the model CS5309. The unit is expandable up to five handsets. The accessory cordless handset CS6909 is compatible to models CS6919/CS6929/CS6949 series. Thank you! - VTech Support
A:AnswerAlicia - The Vtech CS6909 is an accessory handset designed to work with a CS6919, CS6929 and CS6949. Here's the procedure on how to register:
1. Place the new handset on the telephone base.
2. After about 10 seconds, the handset displays "Registering...". When the registration process completes, the handset displays "Registered" and you will hear a beep. The registration process can take up to 90 seconds to complete.
Hope this helps!
-Vtech Support
