Hotfix crystals are rhinestones or other crystal beads with a flat back treated with dry glue. You can apply hotfix crystals to garments or other items using heat from a tool called a hot-fixer. Since the crystals already have glue built in, you require no other adhesives.
In many different colours and designs, hotfix crystals are great for fabrics and other porous materials but you should not use them for leather. Convenient and lovely, hotfix crystals are a costume-design must.