Sartorius ANSI/ASTM Ultra class calibration weights are appropriate for calibrating high resolution analytical balances with tolerances approximately two times the precision of ANSI/ASTM Class 1.

• All weights meet or exceed ASTM specifications
• All mass measurements are made using procedures developed by NIST
• All mass standards are milled from the finest bar steel stock ensuring consistent density
• Each weight is calibrated in a climate-controlled environment
• One-piece construction provides the maximum mass stability
• Each weight and weight set is supplied complete with a Certificate of Conformance
• Certificate of Calibration is available at a nominal cost

Each weight set is packaged in a sturdy storage case and supplied with tweezers for handling to protect against dirt and body oils. Sets consist of flat weights ranging from 1mg to 500mg and knob-style weights ranging from 1g to 100g. Masses from 1mg through 5mg are aluminum; the remainder are of stainless-steel construction.

Certificate of Conformance
Each Denver Instrument weight or weight set is supplied with a certificate of conformance at no additional cost. This report identifies the tolerance class, type of construction and lists the NIST test number and date for the applicable Denver Instrument primary standard(s), the secondary set number and the technician’s signature.

Certificate of Calibration
For a nominal fee, add a Certificate of Calibration to any Denver Instrument weight or weight set by adding a "C" to the end of the part number. The Certificate of Calibration report includes the nominal value and the conventional mass correction value for each weight certified. It will also list information on the standards the weights were compared against including: identifying number, NIST test number and date the standards were last calibrated.