DuraVents DVL Double-Wall Chimney Stove Pipe in Black completes your venting system when used with one of DuraVents chimney products such as DuraTech, DuraPlus or DuraPlus HTC. DVLs double-wall, air-insulated design reduces clearances to combustibles from 18 inch to 6 inch and improves stove performance by maintaining high flue gas temperatures for a strong, steady draft. Because the inner wall is stainless steel, the flue heats up faster, stays hot longer, minimizes the formation of creosote and has the same life expectancy as the chimney, while adjustable lengths eliminate the need for cutting or crimping. California Prop 65: This product can expose you to chemicals including Chromium (hexavalent compounds) which are known to the State of California to cause cancer and birth defects or other reproductive harm.