High precision calibration weights to meet your metrology needs. We offer calibration masses from Rice Lake Weighing Systems, Troemner, Sartorius. Many of the calibration weights can be purchased with an optional Report of Traceability or Certificate of Calibration at an additional cost. Choose from Class 0 to Class F tolerances. Individual weights or weight sets are available in metric or avoirdupois. The correct weight for an application must be more accurate than the precision of the weighing device and must be more accurate than the required precision of your measurement result. It is recommended that a weight have an accuracy that is 1/3 of the measurement device readability and/or your measurement accuracy requirement.