Final answer:
Quad boxes or 4S square boxes are used to join four intersecting conduits in electrical wiring systems.
Step-by-step explanation:
The types of conduit bodies used to join four intersecting conduits are called <strong>quad boxes</strong> or <strong>4S square boxes</strong>.
These boxes have four conduit hubs or openings on each side to allow for the connection of four conduits. They are commonly used in electrical wiring systems to provide a junction point for multiple conduits.