A Kellems grip is a Chinese finger trap-like thing made with steel wire. Those are useful, but are very different from a horse cock.

A horse cock can also be known as an overhead service entrance wedge clamp, which is a surprising mouthful of nomenclature given the parlancial context.

(I don't know what a Hubbell device is -- searching for that just brings up a million wiring devices (outlets, switches, and such) made by Hubbell.

But maybe that's the point?)