Building Entrance Terminals Modules Other Circa’s new line of outdoor Nema 4X protection meets the NEC requirement for outdoor applications, such as construction sites, portable trailers, multi-dwelling units, schools and industrial environments. These units contain Circa’s RDUP/RUS accepted 66 block-style and 110 connectors. They use industry standard 5-pin modules which are sold separately. Termination options also available for BIX. Empty boxes available in both fiberglass and metal.