This is so cool ! I have a hand full of the modern hot-clamp perches in brass. This is the only one I have of this style; older and made of plain steel. This has a solid copper wire that goes in one side and out the other underneath the clamp. Two pieces clip together and make a hinge secured to the perch by the bolt. The Slater bracket ( top left shown in it's installed position) is designed to install on a crossarm from the bottom, in any location regardless of pin locations. It is secured in place by the hinged 'wings' at the top and the screw pin at the bottom used to tighten it.