1, Wiki product http://reprap.org/wiki/PCB_Hea
MK3 choose two working voltage of 12V and 24V, more practical; MK3 uses aluminum plate process, due to the aluminum substrate material is expensive, the cost of production is often ordinary glass plate expensive, so, MK3 price is more expensive.
The new circuit, both connected to 12V, or 24V, have a stable power supply
1, voltage 12V / 24V.
2. Process: aluminum plate
3, Size: 214X214mm
4, thickness: 2mm
5, color: black tbed compatible!