Zinc Die Cast Raintight Box or Fixture Support 3/4″
https://nsiindustries.com/product/zinc-die-cast-raintight-box-or-fixture-support-3-4/
Use Bridgeport 3/4″ Zinc Die Cast Raintight Box or Fixture Support to support an FS box, outdoor lighting fixture, or similar device, per NEC Article 370-23 requirements. NPT threads eliminate the need for sealing rings and locknuts.