HOTFX VACUUM SS6-SS20 APPLICATOR TOOL. BATTERY OPERATED VACUUM Hotfix STONE APPLICATOR with spotlight. Holds & Heats Flat Backed Hotfix Crystals - The applicator tip on the tool works with flat backs in sizes SS12-SS20. WITH BONUS tip for use with flat back sizes SS6-SS12. LED headlights - requires four AA batteries (not included).