3/4" Male NPT to 3/4" Male GHT Stainless Steel Adapter Fitting - Heavy Duty Water Hose Connector for Garden Irrigation, Plumbing & Industrial Applications

This is replacing the brass version of the fitting. 

This converts 3/4" NPT to 3/4" GHT to accept standard garden hose threaded connections. This is what you need to go with the  and  or . 

Here would be your Flow Path if you're doing a stainless inlet hose setup: 

Hose Bib >  >  >  >  >  >  (THIS PART) >  > 3/4" Male GHT Plug > Pressure Washer Inlet