Orbit™ 300 Multipurpose Digital Vortexer,Compact Digital Vortexer. Three interchangeable platforms (available separately) accommodate a variety of sample containers to make the Orbit™ 300 a truly multipurpose shaker. The flat platform, covered with a nonslip rubber mat, holds plates, dishes, boxes, etc. The microplate platform will accommodate up to four microplates. The remaining platform has spring loaded retaining bars that adjust to hold flasks, bottles, racks and other containers in place.