Swarovski Flatback Crystals Hotfix are loose crystal elements with a flat reverse side that has been pre-coated with a heat-sensitive glue. Hotfix crystals can easily be applied with heat using either with an iron (steam turned off) or a hotfix applicator. Perfect for embellishing textile materials for a durable and long-lasting effect. Increased light reflection and a warmer appearance are achieved with a special silver mirror on the reverse of the hotfix crystals . Swarovski Hotfix Flatbacks are available in an extensive range of sizes, colours and cuts, and can be purchased in retail and wholesale packs.