Check the listing for details. Side Arm Heat Exchanger 38.4". Condition: New. Listed at 189.99 USD. Product Description High Quality Fin-Enhanced Sidearm Heat Exchanger is designed with the natural thermo-siphon concept on domestic hot water side. Traditional sidearms are made of two bare copper tubes. Thus, its capacity is decided by the length of sidearm-tubes and the heat transfer efficiency is very low. Made of 304 stainless steel, fin-enhanced sidearm increases heat transfer efficiency significantly by using a finned tube internally, which has surface area five to eight times bigger than bare tube and produces great turbulence on system side. With fin-enhanced sidearm you not only need a shorter unit, but get bigger capacity and faster heating. Typical Applications Ideal for residential heating and plumbing, solar hot water heating and outdoor wood furnace applications. Features and Specs Made of 304 stainless steel Lenght: 38.4'' Boiler Port: 1" MNPT Domestic Port: 3/4" MNPT It increases heat transfer efficiency significantly by using a finned tube internally It has bigger capacity and delivers faster heating ***Mixing valves or Scorch guides are recommended. We sell a SAkit- Sidearm Kit- For domestic hot water systems. This kit includes mixing valve (MV34S or MV34SB), sidearm and a diagram for easy installation. See SKU: SA38Kit or SA38kitSB