After a year of working with students as they design object in TinkerCAD, I found that they have difficulty visualizing in mm and cm scale. Students also loose track of the size of the design as they zoom in & out of the scale of the screen. This 190 mm x 250 mm printable square is great for visualizing the size of larger designs for CNC & 3D printing. The color scale helps with visualizing the size of cm. The coins are to scale (Quarter is 24.26 mm, Penny is 19.05 mm, Dime is 17.91 mm)