For use with various Single line Uniden 5.8ghz PowerMax Phone systems. For use with TRU9460, TRU9465, TRU9480, TRU9485, TRU9488, TRU8860, TRU8865, phone systems. These units will not work with 2 Line units. Please email seller if you do not see your model listed. **To reset the handset with or without the Base Press the Right Red Handset Button & the # Key at the same time until the de-registration mode comes up & select with or without base.**