A project bag can store and keep together the supplies for 1 project– elastics, fabric pieces, thread, buttons,... and with the vinyl window, you can see clearly what’s in the bag. Things don’t fall out, you can take it to a class and it is nice to look at if you use your favorite fabrics. This is not a new, original idea. You can find lots of tutorials online. This is my version. I simplified it a bit so it became a beginner friendly project.