Use approved conduit fittings to protect wires entering or exiting the enclosure. Accessories simplify and enhance cable. As a DIYer, it can be intimidating working with metal electrical boxes. But I'm going to show you a common mistake that people make when wiring them so that you can be confident in making your own wiring safe and secure. But. A junction box provides a necessary protective enclosure for all electrical wire splices and connections, which must never be left exposed within a wall or ceiling. We may be compensated if you purchase through links on our website.