B3-36A 60 Plate Beer Wort Chiller. 3/4″ x 1/2″ Male NPT. 304 Stainless Steel Plates with with 99.9+% Copper Brazing. The description says that this should produce 75 deg F wort with 5 gpm of 68 deg F tap water. Results may be improved with higher cold water flows and lower cold water temperatures.