Photo From: Mark Freburg
Description: Here is an example of scale check weights, this the RCBS Deluxe check weight set. It comes with a set of tweezers for handling the weights, the better to avoid getting one's skin oils on them. In use, one zeros his scale and then uses the check weights to validate the numbers given by the scale. The weights themselves are precision made to laboratory standards.
Both RCBS and Lyman offer these, and perhaps others.
by Mark Freburg