The VTech LS64253 DECT 6.0 Digital technology provides the best sound quality, security and range in cordless phones. Enjoy interference free crystal clear conversations. This unit won’t interfere with wireless networks and other electronic devices. Protect yourself from identity theft with digital security—your call is digitized and encrypted, making it nearly impossible for someone to eavesdrop. Three handsets require only one phone jack.Expand this system to a total of 12 cordless handsets-2 cordless headsets. Audibly announces the name and number of the caller on all handsets and the base unit. The frequency band has been extended allowing for the signal to be reproduced and tuned for a fuller and clearer sound with push-to-talk intercom.