Can anyone identify these reels?

[CatLABS]

i got these with a box of random gear and i cannot figure out what tanks these fit.
it does not seem that they can hold a center core.
also they all seem to fit on top of each other, slightly locking together.

any ideas??

 

[Ian C]

I believe that those are 35 mm Unicolor reels. Unicolor is (or was) located in Dexter, Michigan near Ann Arbor.

The Unicolor tank has the light trap built into the lid, so no core is required to mate with a flange on the top to form the light trap as with other designs.

 

[CatLABS]

Awesome! i think there was a bunch of unicolor tanks that were in the pile, but i did not get...
thanks!