Super easy to build, 1-1/2"-3/4 bell reducer , 10" 3/4" nipple, and another bell reducer. One 3" long 1/4" nipple, coupler and cap, and a .035 mig tip. Drill and tap the 1/4" nipple for the mig tip line it up centered down the 3/4" nipple and tack in place . I used gas rated Teflon tape the yellow one, the reducer at the forge is 3/4"-1"