Abstract: The present invention is a shaftless bi-directional butterfly valve that does not require a valve housing and may be mounted to a length of pipe by merely drilling a hole into the wall of the pipe. A stuffing box is attached to a pipe by a U-bolt or other conventional means. The stuffing box serves as a drill jig to center the hole that must be drilled in the pipe. A threaded rotatable stem is arranged to penetrate one side of a pipe perpendicularly to the axis thereof. In the interior of the pipe, the stem is threaded into a stem nut which travels along the length of the stem as the stem rotates. Its travel is limited by a stop pin which is located at the extremity of the stem in the interior of the pipe. Two elliptical discs are attached to the stem nut, each by a separate hinge pin protrusion, at points which are diametrically opposite.