Made out of stainless steel pipe. Everything including racks is stainless. Made for me by a friend in the early 80's for free. Big company he worked for was scrapping all the materials. The original thermometer on the top finally died and I replaced it and added the two that are at the level of the racks. I have a BGE children gave me for Christmas a couple of years ago, but this will out perform it. Temp climbs to 225-250 depending on gas I give it and remains steady throughout whole cook. I put oak chunks on the wood tray and about a 1.5 gallons of water in the water tray so moisture is in atmosphere of the smoker throughout and constant oak smoke throughout.