Usage Guidelines For best thermal execution: preheat with hot water for 10 20 minutes before adding hot food ( or chill for cold items) Open the pressure release feature 5 minutes before mealtime for easy opening Premium Vacuum Insulation Design Made with food grade double layer insulated 304 stainless steel, this compact lunch box delivers excellent temperature retention for 12 24 hours Full Leak Resistant Construction Incorporates compression vacuum technology with sealing gasket to leaks The discreet carry handle and folding spoon add portability without messy accidents Innovative Press Seal Lid Features a simple push button mechanism that opens with an upward pull and closes with a downward press Large Opening Structure With 16oz capacity, the spacious opening allows easy food placement and thorough cleaning ( hand wash recommended) while maintaining long lasting visual appeal