This 4-grid clamshell bento box is integrally molded from pure food-grade PLA. Thickened partitions, rims and hinges deliver high rigidity with zero harmful additives. It is safe for fridge storage and microwave heating, meeting global food contact standards. Separated grids block sauce cross-leakage; smooth inner walls are easy to clean, and reinforced edges support stable stacking. Fully compostable for home & industrial use, stable quality cuts long-term bulk packaging costs for caterers.