These new boxes are so much fun to give! The box is approximately 5" x 3-3/4" x 1-1/4" and to open you simply squeeze the sides together! These are quick to assemble and cut in one piece for the box base. The file is compatible with both the 8x12 and 12x12 mats. You can see more here: https://jamielanedesigns.blogspot.com/2018/01/squeeze-open-boxes.html