50 plate small brazed water-to-water heat exchanger, 316 Stainless Steel. For use with outdoor wood boilers, snow melt, solar systems, beer wort, bio diesel, and many other applications. Our small style 50 plate is 3" wide and 7 ½ " long! Maximum pressure 435. Minimum operating temperature -265° F, Maximum temperature 392° F. The feed and return is ¾ " MPT. Please see our ads for large size water to water heat exchangers for heating your home and/or domestic hot water. The photo is not the exact unit, but shown at a different size so you can get the idea of what you are getting. If you have questions, please contact us and let our knowledgeable staff help you get your project done right. No need to shop around, buy here with confidence!