How to determine between 93s and 38s
Finding rails for ZD-7 tables
Take one of the four side rails off and measure the spacing between the two outer bolt holes, center to center.
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If your measurement is 28 3/4", then you have the older-style Valley 93:
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If your measurement is 28 7/8", then you have the newer-style Valley/Dynamo 38:
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