More capacity for storage or refuse collection. * Square shape offers up to 14% more capacity than round containers. * Tight-fitting lids help protect dry goods and other contents. * Nesting handles allow secure fit for side-by-side use. * Rounded corners and smooth contours are easy to clean. * Gray and White are USDA Meat & Poultry Equipment Group Listed and assist in complying with HACCP guidelines. * Certified to NSF Std. #2 (gray and white) and Std. #21. * 3517 combo has passed DOT #178.603, #178.606 and #178.608 criteria for shipping of solid regulated medical waste. * Snap-Lock® Lid introduces the ability to collect, transport and ship regulated waste in the same container. * 3530 Casters are non-marking.