is an MDF base material that's supplied with either a thin wooden veneer on both sides or simply painted.
The veneer is approx 0.020" (0.5mm) thick and carving through this reveals the black base colur that works very well for both VCarving and the PhotoVCarve process.
The PhotoVCarved example below is cut into ColourRout - Black base material simply sprayed white, and gives excellent contrast and very visible results. This design is approximately 8" x 5" and cut in around 15 minutes.
It's made by a UK company Moran's Wood Components > http://www.moranswoodcomponents.co.uk
Hope this helps,