Check the listing for details. Hati Rotamixer Vortex Test Tube Mixer Hook & Tucker Biochemistry Bioscience. Condition: Used. Listed at 47.60 USD. HATI Hook & Tucker RotamixerVersatile vortex mixer for the mixing of liquids in a wide range of containers such as test tubes culture tubes and centrifuge tubes up to 40mm diameter.The variable speed control allows a gentle to vigorous mixing range of operation. Continuous or intermittent operation can be selected from a toggle switch, with intermittent action operated by light pressure applied to the rubber cap. The rotamixer mechanism is mounted on a precision ball race in a compact and heavy metal body. Its unique design achieves a consistent orbital movement of the cup irrespective of the loading.Dimensions 15cm (D) x 15cm (W) x 12cm (H)Fitted with 3 pin UK plug​Plugged in and it powers on, rotary knob slows and speeds up. But sold as seen vintage item, One foot pad is missing.