Waterproof conduit generally refers to wall penetration conduit. Wall penetration conduit is also known as wall penetration pipe, waterproof conduit, pre-buried wall conduit, and waterproof conduits are divided into rigid waterproof conduits and flexible waterproof conduits. In electrical applications, those used for electrical conductivity are called alternating current wall penetration conduits, which can be categorized by material into dry-type capacitor-type alternating current wall penetration conduits and porcelain-insulated alternating current wall penetration conduits, respectively abbreviated as silicone rubber conduits and porcelain conduits.