disclosed is a thermoplastic , container for storage of solids , viscous or semi - viscous fluids that permit stacking one upon another for easy shipment and / or display . the container utilizes projections and recesses to engage similarly constructed containers for vertical stacking . additionally , the container includes vertical ribs for enhanced strength . the removable caps used to seal the container include through holes to permit a rigid member to be passed through the length of the openings to apply the necessary torque to loosen the cap . the containers may be variably sized and can be reused .