This Kit fits a 1019801-03 or 39577-03 Vendor Code 3536 Watkins 2 HP Pump and Includes an Impeller, Seal, Bearing, Silicon and Seal Installation Tool... It is about 4 1/8"" across the face edge to edge, it measures about 3" from the tip of the front to the tip of the sleeve in the back, it also measures 7/16" from the inside of the vane edge to edge. Some of these impellers have a number on them B351-21 if yours does you must measure the overall width of the impeller to get the correct one. They cast one implore with that number on it and they trim the impeller down to the different horse powers so be sure you do measure edge to edge...This bearing does fit the motor this wet end works on. 

NOTE: This Wet End looks a lot like an Aqua-Flo Wet End but they do not interchange see the video for how to tell the difference! 

Note: If your pump has a 1019801 or 39577 but no -03 then this is not the correct part..