Abstract: A base structure for receiving an electrical relay is described as being adapted to receive the relay removeably. Electrical contacts in the base connect the base electrically with the circuitry of the attached relay. Terminals are provided for the connection of external wiring to the base and are each connected to at least one of the electrical contacts. Permanent magnets affixed to the base attach the base securely to an electrical panel so that the base is easily removed. According to a modification, electro-magnetism is used to secure the base to the panel. A magnetic shield is disposed, according to a modification, between the source of magnetism and the attached relay.