Well, I'm happy to hear someone else is doing that, taking out a unit periodically when testing multiple units in a cooler. I wanted to see if someone else was using the same thought process. That is what I have been doing when testing 6 units over 12 hours; opening the cooler every hour to two and taking out a unit without the probe until one unit is left at 12 hours. When initially setting up our cooler configuration, I validated a number of different ways, including testing 6 units for the entire duration. Then, the temps held 1-6C for 16-24 hours. Opening and closing the cooler, removing a unit periodically, we were able to validate the coolers for 10 hours, using 12 hour trials. We had our AABB/CAP/FDA inspections in the fall and so far this has been ok with them. But, talking to someone at another institution recently, they were just opening and closing their coolers during validation, not removing units. So, it's interesting to see how others approach this. Thank you.