1638E pump (formerly 1638C) is identical to its predecessor except for a new stainless steel impeller, instead of bronze. Permanently lubricated with a 2 HP, 1750 RPM, 115/230v, single phase motor. Taco 1600 Series pumps are designed for applications that require more GPM flow with larger feet of head. The 1600 Series pumps' rear pull-out feature allows servicing of the pump without disturbing system piping. A replaceable cool running bearing cartridge extends bearing life and permanently sealed grease lubricated ball bearings make 1600 Series pumps virtually maintenance free. A flexible coupler absorbs shock, vibration, and misalignment that could be transmitted to the cartridge and motor bearings. The mechanical seal is an innovative "unitized" design, which combines all of the components of the rotating element into one assembly, making seal replacement quick and easy. Additionally, a one-piece enclosed stainless steel impeller assures long life and higher pump efficiencies.