the 4 in 1 principle for maximum benefit, prepare, serve, store, reheat, 100% hygienic due to high quality borosilicate glass, especially robust and cut resistant, no odors, no discoloration in the glass container, 420°C oven proof, with stacking edge for easy stacking in the same size, 100% leak proof, safe storage and transport, 100% flexible, glass container oven and dishwasher safe