used working Finnpipette Labsystems  pipet multichannel (12 channel) with tips ejector 50 ul-300 ul.   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. If you are not satisfied, you can return the product within 14 days for a full refund excluding shipping expenses.Lot gar21stshclearbx