Abstract: A multi-purpose, extensible, open ended wrench having hexagonal, and/or notched sides used for engaging, loosening or tightening a plurality of various sink and shower drain lock nut designs. Said wrench further has a square hole opposite the open end for insertion of a socket drive handle, and/or extension, to apply torque to a retainer nut and allow access to remote sites. The narrow width of the tool allows for access through small openings in flooring and in locations with little or no other access. The wrench eliminates the need to remove drain pipes, sinks or showers in order to access the drain locknuts.