Each Scienceware contact plate rack holds up to 60 contact plates with lids in a compact and stable configuration protected from knock over and lid displacement. The small footprint preserves benchtop and incubator space, and racks interlock when stacked maintaining stability while preserving additional space. The center handle does not interfere with the samples and provides space for labeling. To maintain sterility and ensure long-term performance, all parts are molded of white polypropylene and are steam autoclavable at 250°F.