I ordered these Dec 2018. I ironed them on to plain cotton sweatshirts for my daughter. It took a couple passes with the iron for them to completely adhere. (I would let them cool in between ironing and check the edges) The biggest test for me was how they would hold up in the wash and they passed the test! Since December they have been washed probably around 10 times. I always turn the sweatshirts inside out, wash on cold, and dry on low. They're still perfectly adhered. Beautiful patches, added a little extra touch to some plain sweatshirts.