This hitch is used in the vertical position, allowing the farmer to attach his plow to a horse or a team of horses. The depth of the plow is determined by which hole is used. (To get a better idea how it's used, click here.) There are many variations of these types of hitches, the common denominator being multiple holes. Ours has eight. Like most old items, the smaller pieces (in this case, the pins) are often lost and replaced with whatever serves the purpose. That appears to be the case with ours and the one pictured below it, which we found online. Even as a makeshift fix, it's missing a nut to hold the pin in place.