From what I see they look like the weights the company that services the elevators at work use for testing elevator car maximum load capacity. I'm sure there are probably many other uses for similar weights.
The Fairbanks one I think was used on a scale arm. Hard to tell on the other one, how much does the first one weigh? I know it said 50 lbs on the weight, but does it really weigh that?
I've seen those used in grain elevators to certify the scales. The Federales (Measurement Canada up here, eh) show up with a truckload of them and start piling them on the scale various amounts at a time and then "weigh" them. The beam scale should agree with the know weight on the scale pad...plus or minus the allowable error percentage.
From what I see they look like the weights the company that services the elevators at work use for testing elevator car maximum load capacity. I'm sure there are probably many other uses for similar weights.
Yep, thats what I have seen, the exact same weights used by the elevator guy to certify the elevator. I suppose they could be used for any purpose to certify any scale or whatever.