Eastern Sheet Metal Single Wall Round Spiral Pipe and Fittings are available in 1" increments from 3" diameter to 30" diameter and in 2" increments from 32" diameter to 84" diameter. Our single wall duct is avaiable with a variety of connectors including Eastern Tight and Eastern Flange. ESM spiral is available in G90 galvanized steel, paint grip, types 304 and 316 stainless, 3003 aluminum, plus Eastern PCS for cost effective underground and fume exhaust. Eastern spiral is also licensed to bear the AMCA Certified Ratings Seal for Air Leakage.