With these boxes, a bit of high temperature silicone around the wire is usually all you need to seal the box, and some canned foam to seal the box to the wall. Henkel's polyurethane or silicone sealing foams protect the electronics in control cabinets and electrical distribution boxes against external influences, such as moisture and dust, which can cause against corrosion and contamination. However, the key to. A distribution box, also known as a distribution panel or board, is a cabinet that holds electrical parts used to supply power to multiple circuits within a system. Today, electrical systems are essential for homes and industries. a) foam, ensuring that NONE of the foam encroaches on the volume of the electrical box.