I have a small collection of frog eyes and picked this one up because it was weird. Does anyone know how this was used. Seller from Toronto wasn't sure how/where it was used. Thanks for any help!
James Mulvey provided some additional info. According to his research, this harness (referred to as a hot clamp perch) would have been attached to a Slater bracket. The insulators were installed sideways so that the perch was horizontal. Here are some complete sets he's found in the wild along with additional info:
[id=483705308] [id=483643997] [id=249993140]