The siphon is a must for the steam pressure gauge when used with steam (not needed for air service).  We carry 2 sizes:  They include a banjo fitting and adapter to fit 1/8" NPT, or 10-32 in the boiler or other vessel.
         
        
          
        
     
   
 
  
  
Use left/right arrows to navigate the slideshow or swipe left/right if using a mobile device