Review on 24V 250W HICTOP MK3 Aluminum Heated Bed Hot Bed PCB Heatbed Platform For Reprap 3D Printer - 275 X 220Mm by Fred Griffin

This bed is one of the few largest all in one heated beds out there. Anything bigger, its likely not heated and requires an external heat element.Be aware while its flat, it may have a 50-100 microns variance between the center and the perimeters. If you rely on mechanical end stops, this will be a problem, if you use a inductive probe with auto bed level, then you wont have a problem.I have used a 8x10" glass sheet on this and it worked good when i didnt have a Z probe, as the glass took care of the uneven-nes.But i later I purchased a 8x10" BuiltaK sheet and installed it directly on this bed, and its the best configuration i have found using a Z probe.I can achieve 55 deg C in less than a minute and 85 degrees in under 2 mins.