I made this death trap in 2005.
It is 118 mm. tall, 143 mm. wide, 13 mm. thick, and weighs 357 g.
After seeing the open sidewinders and noting how they could attach to the seat harness without requiring a maillon or carabiner, I wondered if one couldn't make an open version of the longhorn that would do the same. Making one was easy, but it does not work. Without the horizontal bar, there is nothing to keep the rope in the device - and the rope will come out, trust me on this. Do not make one of these.
This is one of my most idiotic inventions and I deserve the Lemon Award for it.