22168 Fisher HD Heavy Duty Plow A-Frame MM1 Minute Mount

Fisher A-Frame # 22168.

This is used on the HD Fisher plows. Between the brackets it measures 22-1/2" as you can see in the diagram below. This is for the older MM1 plows these are the plows that you have to walk around both sides to pull the pins. This attaches to the blade with a 1"x6.5" pin. 

For a breakdown of related parts, check this link.