The RA400 Medical Alert System is the MXD’s predecessor that entered the market in 2000. This reliable RA400 model continues saving lives today. The sleek and attractive medical alert was designed by Rescue Alert engineers with your protection and comfort in mind and is the heart of your medical alert system. Because sound quality and clear communication are extremely important for alert systems that aid senior monitoring, Rescue Alert offers an extremely powerful microphone and speaker that flawlessly connects your home with our Response Centers. Such noteworthy features of the RA400 have proven so beneficial they set the standards for all new Rescue Alert models