A used working variable volume Gilson pipetmans -set of 3 pipetmans P1000 (100-1000 ul), P200 (10-200 ul) and P20 (2-20 ul) . All the single pipets are in the old style (not rotating/dialing top knob) with tip ejectors,.The pipettors sold have been used only with non-radioactive and non-biohazardous materials. Also, all pipettors have been tested to work properly- I have measured the aliquottes on a Mettler scale. Some pipets available separately- please inquire. If you are not satisfied, you can return the product within 5 days for a full refund excluding shipping expenses.