Aqua-Flo XP2 2.0HP (4.8 BHP) - 2-Speed Flo-Master - Spa Jet Booster Pump

• Supercedes all XP2 Pumps with the Century LASAR Pool/Spa Motor with AO Smith motors.

Specifications:

• Flo-master xp2 2.0HP 2-Speed 
• (4.8bhp on some spas) <---Most Common Size (90% are these)
• EMG Elettromeccanica
• Height: 197-235mm
• 2"/50mm FBT Thread - measures ~78-79mm OD on pump

Other part numbers this supersedes: 8 - 194082 - 40. 06120223-1, 97452010, Code 01291, Part 7 186364 02, 06120070-1

Notes about Horsepower Ratings: 

• Some Spa Manufacturers use a complicated & confusing form of Horsepower measurement that was more commonly used in the USA, called hydraulic horsepower (HP=PSI*GPM/1714). It gives a more impressive appearance, and may give a false impression of performance. 
• Standard Australian HP ratings are calculated purely on input power in Watts, which are then converted to HP. (1HP=745.7Watts). 
• You can always measure (with an Amp Meter) the input current and convert back to real HP.
• Rough HP measurement can also be calculated using Ohm's Law (V=IR).  These pumps also have an Amperage rating that can be roughly converted back to Watts, and then to Horsepower. The problem here, is some spa manufacturers used slightly misleading ratings here as well, eg, they'd use a locked-rotor Amperage draw, etc. You'll see how the Amperage ratings and the HP labels don't match up.
• Furthermore, HP ratings are not an ideal measurement of pump performance anyway! Pump flow curves, which measure flow per metre of head pressure are a far more reliable method of measuring pump performance, especially with the advent of variable-speed DC motors.
• Basically the labels can appear to be very different in regards to the pump's actual HP rating.

Examples: Some Balboa Pumps marked "4HP" is actually a 2HP pump in Australian terms. Some Aquaflo Pumps labelled as 4.8BHP are 2.5HP in Australian terms.