!2" Ceramic Tile

I got a 12x12 granite tile from Lowes and had it cut into 6x6 squares in the store, for less than $20.  I used granite because it is flat on both sides, all of the ceramic tiles had ridges on the bottom.  It was heavy enough that I didn't even bother clipping it.  It works well, but takes a long time to heat up.  Glass works well enough so I stick with that.

Pcpoirier, do you want a tile with the holes drilled for the bed leveling screws?