WHAT ARE DUAL'S WORTH?

I bought a pair of Mexician Hat duals with rims at an auction last month for $150. He was asking $400 for them a year before the auction. I'm told that both prices were a good deal. I'm planning to use the duals on my 220.

I think we have some confusion about the term mexican hat dual hubs. According to Swinford, Mex. Hats are the 350# casting that axle mounts with six bolt wedges and provides an outside Dia.to hold 38" double bevel rims with 16 clamps, or power adjust rims with 8 clamps.  NOT the lighter 120# castings that bolt to the six bolt 16" Dia. bolt pattern on the inner wheel casting and provide a nine hole hub to mount a 34" die formed outter wheel rim. Mex. Hat's were first made to be used on 220/210 tractors and later carried over into the 7000 series.  I would think that they would work on any AC tractor W/six bolt wheel wedges and enough axle length. I'm thinking there is some confusion based on the prices given for the Mex. Hat dual castings.

The duals that I bought were the heavy 38" with the 350# cast centers and double wedges that Dale mentioned. I have the smaller 34" set with the 9 both pattern for pressed steel rim duals on my D-21. What is the correct terminalogy or name for each?

Neither of those are mexican hat duals, the bottom looks like a long axle tractor with 2 standard cast centers.  Mexican hat duals are like the standard cast centers, but just imagine the center of them being "punched" so that it is offset.  I tried to find a picture on google, but couldn't find any in my quick search.