I don't know what they are called, but my dad used a set of these when towing his travel trailer in 1963. I used them in 1990 towing our first pop-up. I used them again for our first TT with our Suburban, then when we got our first dualy truck, the mirrors extended, no longer needed these. Somewhere over the last 2 or 3 moves to new houses, they've gotten lost. But they do work very nice. They clip under the hood and onto the wheel well fender. Then the turn-buckle tightens them down. I do remember there was a bit of shake, but after 40 years of use, I suppose they had a right to be a bit shaky. Funny, these haven't changed a bit in 40 years, except for that plastic knob to turn the turn-buckle. My old set did not have that knob.
