HeartSine samaritan PAD 450P AED machine offers an integrated CPR Rate Advisor that uses only the electrodes to monitor and uniquely provides visual and verbal feedback on the rate of applied CPR, as well as continuously reminding the rescuer to perform CPR when no CPR is detected. HeartSine's exclusive technology effectively assists the rescuer to perform CPR – a key link in the chain of survival. *REPLENISHMENT Accessories are also available!