Just met with the Zoll regional reps for our area 2 days ago and discussed the NIBP failure history during both ground and air transport. They have a new NIBP module for the M-series that should be better. It has new hardware and software and they are developing a new tubing with a steel coil similar to the Nutone stethoscopes. We will be testing one of the M monitors with the updated NIBP in our aircraft and on ground ambulances at one of our local Fire Dept's. You might want to contact them about this too.