8 ounce NIST Class F highly polished stainless steel..
Stainless Steel Class F Test Weights are primarily used to test commercial weighing devices by state and local weights and measures officials, device installers and service technicians. Stainless Steel Class F Test Weights may be used to test most accuracy Class III scales, all scales of Class III L or IIII, and scales not marked with a Class designation. Class F is also acceptable for use verifying scales that have 0.1% accuracy or lower. Stainless Steel Class F Cylindrical, Cube and Grip Handle Weights are legal for trade, which means their design meets specifications as outlined in NIST Handbook 105-1 and are approved to be used on legal for trade devices within the United States. Weights 5 kg / 10 lb and below must be made of stainless steel of quality not lower than 300 series stainless steel.