The machine thread magnetic drain plugs covered by this specification are intended for use in engine oil lubrication systems as a means to seal and access the engine oil reservoir and to magnetically attract and capture ferrous contaminants in the engine oil that could result in accelerated engine wear.

Type I. Type I machine thread magnetic drain plugs feature an external hexagonal head that provides the surfaces against which torque is applied when loosening or tightening the drain plug (see figure 1).

Type II. Type II machine thread magnetic drain plugs feature a circular flange with an integral hexagonal head into which a 3/4-inch square drive slot has been incorporated (see figure 1). Either the hexagonal head or the square drive slot may be used to apply torque when loosening or tightening the drain plug.