Found this metal detecting.
It is Super heavy by The way. Cant even pick it up with one hand. With two hands Its just heavy. What Do u think it is? What are those lines in picture 4 and 5?
I looks like part of a PTO shaft. Power Take Off, the missing part slips on a splined shaft, 560 or 1000 rpm. They can have a clutch mechanism and shear pins and a few different safety parts also.
It’s how you power up the implement your pulling threw the field.