If you make one, make sure you don't use fabric with the shiny gold or silver on it. They will catch fire for sure. But I have two that I made -- one for baked potatoes and one for warming tortillas. They work great as long as you are very careful that they do not touch the sides of the microwave or that you don't cook in them for longer than 4 1/2 minutes at a time. If baking potatoes, you can stop after 4 1/2 minutes, let it rest for 30 seconds or so and then start the microwave again. It only takes about 30-45 seconds to warm tortillas -- no more frying them ever.