Found this old piece in a lake. 5" long x 3 3/4" across. About 1" thick. Appears to have two holes for screws on both sides of the larger hole. Quite heavy. I'm wondering if it was on the nose of a boat and two rails went over the two lower ears.
For the life of me, I can't remember which piece of farm equipment that goes on, but it may be the mounting bracket for the parting board on an old sickle-type mower? I am 99% sure it is off of farm equipment though.