This Quill A3 Board is perfect for school projects, card making, signage and more. It has a thickness of 210 gsm and is acid-free so you can use it with a wide range of art supplies. It has a thickness of 210 gsm making it sturdy and durable. It's A3 size which can be used as is or cut down to size. There are 15 sheets of board in this pack. It's acid-free so it won't react with your art supplies.