Tool Wrap Features Reclosable Carton Function Helps Protect from Scale and Oxide Buildup During Atmospheric Furnace Heat Treating Protects Surface of Air Hardening Tool Steels Creates Airtight Envelope Around Part Can Use in Furnaces up to 2240 Degrees F Material 309 Stainless Steel Resists Chromium Carbide Precipitation During Exposure to High Temperature Thickness 0.002 in Width 12 in