[Milsurplus] Question about GRC-109

[w4ron at carolina.rr.com]

I wonder if there is a GRC-109 expert in the group?
I've found a set that appear to be in like new condition.
I've done a Google search and everything I find shows
there being 3 units, but the set I've run across has
4 units. All 4 sections has it's removable cover,
Included is a package of cables that look like they'd
go with the set.
I've uploaded some photos of the 4 units together
and then a separate pic of unit.
You can see the pics here, just scroll down a little;

http://radioheaven.homestead.com/McCall-collection.html 

Any advice as to what I've found and what they might
be worth would be much appreciated.



--
73, RON w4ron
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