4" Diameter stainless steel pump, motor shell, and drive Shaft. Quiet and economical operation. Submersible pumps are rated on the average number of gallons delivered per minute to the well head from various water level depths. Models rated at 10 GPM are for the average residential size home and family. Manufactured by flints & walling, all Star pumps use the contractor recognized water lubricated Franklin motor. Cast-iron discharge, Lightening protection. Easy heat-shrink Splice kits included in package along with illustrated installation instructions. 1-1/4" Cast-iron discharge.