These paintings are painted on 11" substrates that are 3/4" thick. The first 30 or so are painted on a birch plywood and others on MDF. I had them custom made by Captive Cutting in Leduc, AB. Both birch and MDF panels are great to paint on, with MDF panels being smoother. The substrates are small and at this size, birch and MDF do not weigh much. I make sure that they are sealed on the side (very important for the MDF panels as the sides are more porous and absorb moisture) and gessoed before I paint on them.