210 kBTU Titanium Shell and Tube Heat Exchanger for Marine/Swimming Pool/Solar/Spa Capable of 210,000 BTU/hr heat transfer Titanium construction perfect for chlorine or salt water pools and spas Use with solar collectors or conventional boilers for heat supply Tube Side Connections (Straight-Through/Boiler or heat source): 1-1/2" FNPT Shell Side Connections (Side Outlets/Pool): 1-1/2" FNPT