[R-390] Slightly OT: RF Coil Can ID's

[John KA1XC]

Hi and Happy New Year group,
while sorting out a new junk box of parts I came across a bunch of slug
tuned coil cans that are very close to the Zxxx coils used in the R-390A.
They are almost identical in appearance but have different reference
designations, frequency spans, part numbers, and the number of pin
connections vary too.

I don't own any Collins gear other than 390's but I'm guessing they might
have been used in some of their other HF equipment.
Anyone recognize these things?
thanks,
John

Z4    1.7-3.7 MC    543-2981-003

Z8    3.7-7.7    543-2985-903

Z12    15.7-31.7    543-2989-903

Z23    7.7-15.7    543-3000-013

Z22    3.7-7.7    543-2999-903

Z25    2-4 MC    543-3002-903

Z26    14-28    543-3003-903

Z27   14-28    543-3004-014