One used working Thermo Finnpipette pipet F2 pipet fixed volumw 200 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 gar1shshYelbx