Junction Box Helper!

- Junction Box Helper - The best junction box calculator on the app store Junction Box Helper is the only application that you will need to size electrical boxes This application is for conductors 4 AWG and larger. This tool is fantastic for sizing junction boxes in the field or in the office. NFPA, National Fire Protection Agency, National Electrical Code, NFPA 70, and NEC are registered trademarks of the National Fire Protection Association and are not associated with ReiWare, LLC in any way.