Get ready for some numbers:

To determine the usable area of each of our three standard depths (24, 32 , 40cm, and for select products 50 cm), you have to deduct the thickness of the front and back panels.

For the Type01 Plywood, the front panel is 16 mm and the back panel is 12 mm which means you would subtract 28 mm from the depth. For the Type02, the front and back panels are both 18 mm, so you would subtract 36 mm, and for the Type01 Veneer you subtract 34 mm, as the front panels are 16 mm and back panels are 18 mm.