These 600 series syringes are rugged, durable and long lasting. They have a reinforced plunger, which prevents plunger bending. The plunger is individually fit to the glass barrel and can not be interchanged between syringes. Recommended for use with liquid handling. All have removable needles. Needle gauge is 22s. Maximum temperature is 115°C (239°F). Maximum pressure rating is 2000 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.