This document provides specifications for various distribution boxes including dimensions, mounting sizes, and number of ways. No matter how ha sh the environment is, there is always a proper enclosure for your needs. Thanks to protection ratings and high quality ble (from 65 x 65 mm up to 361 x 254 mm) plus 3 different cover hei xes are available. Wiring diagram shows both PNP and NPN wiring. Actual units use PNP status indicator, NPN status indicator, or neither. Dimensions are shown in mm (in. All boxes are made from robust polypropylene (that will never rust) and are. These Distribution Boxes enable decentralized installation of the electronics close to the load. SMART DISTRIBUTION BOXES FOR FLEXIBLE BUILDINGS.