The WXB is a multistage, diffuser-casing barrel pump with tandem impellers and a balance drum to carry axial thrust forces. It is designed for users who need the hydraulic range and performance of a ring section pump, but demand the design and maintenance attributes of a barrel pump. An extension of the well-proven WXB, the WXBB is an API 610-style, multistage barrel pump which incorporates Barske style impellers to produce stable low-flow performance. It is a reliable, direct drive solution for low-flow, high-head applications.