Abstract: Slot interlock connectors for RF welding electrodes include an electrode having a working edge, at least two ends and an integral mounting block which has ends which overshadow the ends of the electrode and provide substantially flat alignment surfaces adjacent to the ends of the electrode. The electrode may have a curved or straight working edge and the integral mounting block may be disposed on the interior concave surface of the electrode or the exterior convex surface of the electrode. According to the invention, the electrode can have one, two, three, four, or more working edges with one, two, three, four, or more integral mounting blocks. The ends of the mounting blocks overshadow the ends of the electrodes and provide substantially flat alignment surfaces or alignment channels adjacent to the ends of the electrode. Several embodiments of connectors are disclosed, including connectors having L, T, +, and * configurations.