Tulip Glam-It-Up! Hot-Fix Glass Crystals 100 pack - 3mm/4mm/5mm - Tulip Hot Fix Crystals are made from high-quality, glass crystals. They aren't acrylic, so they won't lose their lustre in the wash. Truly easy to use - just set your design and Iron On. The crystals are machine washable. So now you can create your own fun, fashionable, sparkle designs. This package contains 100 rhinestones in three sizes 3mm, 4mm and 5mm.