What are the game boards made from?

The game boards are made out of 2mm greyboard and wrapped on both sides with 250gsm paper with a matte varnish as to not reflect too much light. All edges will be wrapped and there are 10 of these boards in the box (5 x Terrain Tiles and 5 x Store Tiles). It would have been much cheaper for us to produce a single game board rather than 10 separate game boards, but separating the boards adds a HUGE aspect of modularity to the game!