Abstract: An electrical connector assembly is installed on a plate having a polygonal through hole and composed of an external rotating member, a locking rod, an outer tension ring, an inner tension ring and a locking part. The relatively larger sized external rotating member, the push handle shaped outer wall and the ridge pattern for durable handheld operation provide an easy convenient operation for both reverse or forward rotations. The outer tension ring has a multi-protrusion block plugged into a polygonal through hole of the plate and a polygonal groove of the inner tension ring to achieve the effect of engaging with the polygonal plug and the locking rod is screwed with the nut and the locking part to achieve the pressing effect, such that the outer tension ring, the plate and the inner tension ring can be pressed and attached securely with each other.