The deceptive advertising of jack-stands involves combining the rating of two stands into one "spec". So two five-ton stands = "10 ton" jack stand (pair.)
But those don't even look like "5-ton" (each) stands.
The holes in the saddle casting may be intended for suspending a piece of pipe between a pair of stands for unreeling spools of wire and cable. (I don't know who made them though)