While these are nowhere near the weight of an official ultimate frisbee, they are still thick plastic, really great quality and fly very well. I bought these for my son's birthday party for his friends to decorate with permanent marker before they get picked up by parents. They are perfect because they are completely blank. The stickers on the front of the frisbee come off very easily, the ones with a barcode on the underside do not. So, I just left those ones on.