The Hamilton 900 Series Microliter syringe manufacturing process is the same as the 700 and 800 Series (S7905 & S7910) which incorporate a stainless steel plunger hand-lapped into a controlled barrel diameter. This series was developed with an extended metal sheathed borosilicate glass barrel and strengthened plunger stem which acts as a support guide for the extremely fragile, small diameter plungers. Maximum temperature for Cemented Needle 50° C (122° F) and Removable Needle 115° C (239° F). Maximum pressure rating is 2000 psig except for 250µL which is 1000 psig. These Hamilton syringes can be ordered with a Certificate of Calibration. The Certificate of Calibration will be provided with the product and the procedure is performed with an unbroken chain of calibrations traceable to N.I.S.T. Please request at time of purchase.