For installation on the suction side of engines and pumps, GROCO SD Series raw water strainers are the ideal filtration solution for heavy-duty cooling water intakes for marine engine, ac unit, or genset. The design makes them long lasting and easy to service while the variety of sizes means there is a fit for larger size installations. In production for more than 50 years SD series strainers are designed with a durable cast acrylic sight glass, bronze head castings and the choice of flter basket materials - #304 Stainless Steel and Monel. SD strainers are offered in 1-1/2", 2", 2-1/2", and 3" NPT pipe sizes.