PF-40-2N22C This is the 12 amp version, 2-speed, with same size threaded connections in and out, 3" outside diameter threads. Actual thread size measures 3.065" or 3-1/16", PF-40-2N22M, PF402N22C
3721621-1D Waterway Spa Pump 2-speed, 230V, 12.0/4.4A Executive 56 frame 6.5" diameter 2" SD/CS. Threads measure 3.1" outside diameter. PF-40-2N22C, High performance Water Way Hot Tub Pump, very strong motor, split capacitor design, double shielded ball bearings. Viton Seals. Overall length=17" Labelled 4.0HP but often relabeled 5hp, 6hp, and even 7hp. 37216211d P240E52024, PF-30-2N22M, PF402N22C. Intake and discharge threads are same size as each other and 3.1" outside diameter.
Overall length 16-7/8", height 9", width 8-1/4". Energy Efficient, labelled 4.0 HP, often marked by spa manufacturers as 6.0 BHP, which is the maximum brake horsepower it can produce. Spa Pumps, Hot Tub Pumps; sometimes ships with US Motors/Emerson motor, and sometimes with A.O. Smith/Century motor. , PF-40-2N22M, PF-40-2N22MC, PF-30-2N22C, PF-30-2N22M, PF-30-2N22MC, 3721621-0D87, 3721621-0D36, 3721621-0D, 3721621-0D76, 3721621-1D5A, 3721628-0D85LB, 3721621-0D76VK, PF302N22C, PF-50-2N22C, 3721621-0D85, PF402N22M, Massage Master XLT, R63MWENA-4727
PLEASE NOTE ON WIRING: we do not know what color wire your spa control uses for high speed and low speed. The photo shows locations indicated by your motor diagram on the label, on the side of your motor, and is for your reference only. We are not suggesting black for high or black for low, this is not determined by the motor, it is designated by your control. If red was high speed for you in the past, it is still the high speed wire now. Some controls use black for high, some brands use red. If in doubt, call the manufacturer of your control, or use a voltmeter to determine.