The muchmore unit uses only one 30mm peltier. The other thing they should include in their cooler is thermal grease between the clamp and the peltier for greater cooling.
In my units I use two 40mm peltiers wired in series (one cooling the other) for greater effect. I have sold many of them so far. Although a little larger in size, they are much more effective. They have been tested side by side and several of my buyers have sold their much more units to get one from me.
The muchmore unit works great and they have an incredible high speed fan, blowing air on the heatsink. However, it doesn't work super well in warm air temperatures as the fan then struggles keeping the heatsink cool due to it's size. The smaller peltier also works very hard to keep the clamp cool.
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