[TowerTalk] Turnbuckle Manufacturer

[Byron]

Hello-
   Possibly someone here that has worked around towers for a good while may have knowledge of the manufacturer of a certain type turnbuckle. I have seen these before in some old-timers stuff but never knew who made them.
   These particular ones are ¾” x 18” and have the large circular eyes like the Chicago ones. The bodies are different than most other ones in that they have rods (approx. 3/8” or so OD rods) for the side members rather than rectangular sides. They appear to be of good quality and have a good thread fit (not sloppy) with good centering. The only marking that I can find is a small “3/4” stamped on one end of body.
    The reason I ask is that I am considering using these on a tower project (140’ 45G) with mixed ¼” and 5/16” guy wire. I realize 5/8” turnbuckles would be specified but I have an opportunity to pick up enough of these NOS ¾” ones to fulfill my needs. I am a little concerned in using something that I do not know the manufacturer or origin.
    Thanks,
    Byron W5FH