In various representative aspects, an assembly for connecting and electrically bonding two solar panel rail guides is provided. More specifically, the assembly provides a novel and improved inner rail used as a splice that slides within the two solar panel rail guides and includes a serrated screw that is pre-installed within the splice. When installed, the two rail guides are brought together along the splice and meet at the point where the screw is located, the screw can then be tightened so that the serrations penetrate surface treatment layers on each of the rail guides so that the solar panel rail guides are secured and electrically coupled to each other. An alternate embodiment utilizes the inner splice to join two solar panel rail guides by sliding the splice within the inner contour of two solar panel rail guides, and utilizing a pair of bonding pins to electrically bond the splice and the two solar panel rail guides. A stop pin inserted into the splice provides a tactile connection point where the two solar panel guides can be joined together.