Amazon.com: Baltic Birch Plywood, 3 mm 1/8 x 12 x 24 Inch Craft Wood, Box of 12 B/BB Grade Baltic Birch Sheets, Perfect for Laser, CNC Cutting and Wood Burning, by Woodpeckers :
1/4" Premium Walnut Laser Cutter's Pack with MDF Core, 4 pieces (Choose Your Size) - Woodworkers Source
Baltic Birch Plywood, 6 mm 1/4 x 18 x 24 Inch Craft Wood, Box of 8 B/BB Grade Baltic Birch Sheets, Perfect for Laser, CNC Cutting and Wood Burning, by Woodpeckers - Walmart.com