Yoke plate is also called clevis plate. The yoke plate is string hardware which used to couple the electrical clevis, socket tongue or insulators. We often see the yoke plate on overhead power lines, power transmission lines.
The yoke plate is installed to attach the insulators to the cross arm on one hand and to the conductor termination on the other hand. According to the shape, there are triangular yoke plates, rectangular yoke plate, and irregular yoke plate.