Die Cast Zinc Offset Conduit Nipple 2-1/2″, NPSM Threads
https://dev.nsiindustries.com/product/die-cast-zinc-offset-conduit-nipple-2-1-2-npsm-threads/
The Bridgeport 2-1/2″ Die Cast Zinc Offset Conduit Nipple serves as a short raceway between two raceways, enclosures or boxes with different axes. Offset nipples are used to offset a conduit system with different axes.