Extremely popular pump wet end by Waterway, 1.5" Wet End suitable for most applications as original equipment, and for universal replacement. This wet end is found in tens of thousands of spas and hot tubs worldwide. Ratings from .75 to 2 horsepower. This wet end has 4 screws in the front cover. Suction and Discharge threads measure 2 1/2" diameter overall. Find replacement instructions at SpaSupport.Com Pump Seals Impellers