Review on 💨 High Performance TEC1 12705 Thermoelectric Cooler Peltier with Maximum Power of 77W by Mike Wallace

Last month I used 2 of these and they both worked fine. I highly recommend checking which side is hot by touching the 9v battery leads (red lead to positive) before installing. For both elements I used, the hot side was the unmarked side. I believe the industry standard is the marked side to be hot. Maybe they were tagged on the wrong side. So test first. Not a big deal, which can explain the low price.