LAING E-Series Circulation Pumps E-3 115/230v 27W drive unit Direct replacement for all SM303 motors. Simply unscrew the old motor, and install the new E-3 drive unit into the existing SM-303 volute. Re-connect the electrical cord, and you are done! *o-ring not included Volts Watts Manf# 115/230v 27w E3-N3-13 (7405) Replaces: SM-303-NH/T 115V 33W 1/2"B x 1/2"NPT 4gpm (Keep the old volute!) SM-303-NH/T 115V 33W 1/2"B x 1/2"NPT 4gpm (Keep the old volute!)