Reinforced walls add strength and rigidity and wide top ledge permits stable, higher stacking. Constructed of water and corrosion proof polypropylene, they withstand freezers and autoclaves from -40F to 250F. FDA Compliant Resin & Colorant. Front, back and side grips allow easy handling. Molded-in full-width rear hanger lip allows bins to hang from louvered panels or rails. Anti-slide stop prevents shifting when stacked. Slotted label holders allow easy identification of contents. Made-in-USA.