The AGL15FL2CS is a specific model of spa pump motor manufactured by U.S. Motors (a brand of Nidec, formerly associated with Emerson and A.O. Smith).
It is a versatile, 1.5 HP, 115V, 2-speed, 48Y frame motor designed to be installed as part of a complete pump assembly (motor + "wet end").
Because this is a general, replaceable motor used across the industry, it is compatible with pump "wet ends" from several brands and, consequently, appears in spas from many different manufacturers.
Manufacturers of Compatible Wet Ends/Pumps
The AGL15FL2CS motor features a "thru-bolt" design, which means it attaches to the "wet end" (the part that moves the water) using four long bolts. The motor itself is a generic component used with different brands of wet ends:
AquaFlo (a division of Gecko)
Waterway
Hayward PowerFlo
Dynamo
Spa Manufacturers Using This Motor/Compatible Pumps
The various spa manufacturers listed below have installed complete pumps (with this motor or a direct equivalent) in specific models of their hot tubs:
American Whirlpool
Cal Spas
Coleman Spas
GG Industries
Sundance Spas (certain models)
Brands associated with the above pump manufacturers and large retailers.
The exact spa manufacturer often depends on which pump wet end (e.g., Waterway, AquaFlo) is bolted onto the U.S. Motors AGL15FL2CS power source.