I’m not sure if there’s a better spot for this question, but can anyone tell me what this is/what it’s used for? What kind of steel? These are on opposite ends of the rod and it’s 5-6 ft long. Thanks!

Looks like a curb stop wrench.  

Or 'stop tap key' I know them as in the UK, the spade end for cleaning out any silt that may have accumulated in the stop tap box.

May be as much as a medium carbon steel but low carbon would be my guess until tested.

Makes sense! I’ve never seen one with a spade end before. Thanks!