HeartStart MRx defibrillator/monitor.
Model numbers M3535A and M3536A with Q-CPR™ meter option B08.
Specific serial numbers affected.
Affected MRx units have to meet all of the three criteria below:
serial numbers from US00100153 to US00571587 inclusive
the Q-CPR Meter Option B08 installed
Software revision F.xx, R.xx, T.00.00 or T.00.01 installed