Ordering Description Product number Description: Tweco WC56EL-H Gas Diffuser, Brass, Eliminator Product number: 1560-1147 Description: Tweco WC56EL-SW Gas Diffuser, Brass, Eliminator Product number: 1560-1146 Description: Tweco SW54-EL Gas Diffuser, Brass, Eliminator Product number: 1540-1116