Bronze Circulator Pump, 3/4" Sweat, 1/25HP, 115VBronze Circulator Pump, 3 4" Sweat, 1 25HP, 115V Grundfos UP15 10B7 is a 1 25HP Bronze Circulator Pump with 3 4" Sweat inlet outlet connections. Sweat connections of the UP15 10B7 model simplify the installation process and eliminate the need for purchase and installation of pump flanges simply sweat the pump into the 3 4" copper line. Bronze circulation housing protects the pump from corrosion and allows for use it in different applications, such as