UltraCruz® Vortex Mixer has a powerful motor, which results in smooth, instant mixing of fluid samples for various laboratory applications. Vortex Mixers operate at variable speeds from 200 to 3200 rpm and accommodate tubes up to 50 ml in size. Vortex Mixer includes touch or continuous operating modes that are smooth, quiet, and efficient. Mixer is equipped with "no-walk" suction feet to avoid sliding, cold room/incubator compatibility, and spill-proof electronic controls. Vortex Mixer Flat 3" head attachment is suitable for general vortexing purposes. The flat foam head of the attachment provides a large contact area for items to be mixed. Vortex Mixer Combo head attachment is perfect for vortexing microcentrifuge tubes and microplates. It can accommodate 38 (0.5 ml) microcentrifuge tubes, 28 (1.5 or 2.0 ml) microcentrifuge tubes, or one microplate. Vortex Mixer Horizontal head attachment is used for vortexing 15 ml centrifuge tubes. The four brackets allow for mounting of 15 ml centrifuge tubes in a horizontal position.