TEC1-12703 Peltier Thermoelectric Cooler Module 40x40mm

A Peltier module cools (or heats) using the thermoelectric effect rather than any refrigerant or compressor - applying current across 127 internal semiconductor couples pumps heat from one ceramic face to the other, creating a genuine temperature difference with absolutely no moving parts, vibration, or noise. Reversing the applied polarity flips which face gets cold and which gets hot, so the same module serves as either a cooler or a heater depending purely on how it's wired.

Rated for 3A at up to 15V (30W maximum), it delivers up to 18W of refrigeration power at its rated operating point, and the standard 40x40mm form factor matches the heatsink and fan mounting hardware widely available for this module size. Because a Peltier module's hot side gets genuinely hot, pairing it with an adequate heatsink and fan isn't optional - without one, heat backs up and the module's cooling performance collapses or the whole assembly overheats.

Common uses are small DIY cooling projects (mini fridges, CPU cooling experiments, camera sensor cooling), portable heating/cooling combo devices exploiting the reversible polarity, and educational demonstrations of the thermoelectric (Peltier) effect.