These motors are direct replacements of the "original" motors that came with many pump brands. No pump manufacturer produces their own motors. When the motor is removed or replaced, always replace the mechanical shaft seal. If you do not change the shaft seal, you are risking water damage to the new motor and voiding the warranty. Keyed shaft 56 frame (A.K.A. C-face or round flange) motors fit most of the older brass pumps that you may still find from time to time. It would be wise to consider replacing the complete pump instead of the motor on these pumps as the newer models are far more efficient.