Abstract: A surface mountable reed switch, which is particularly useful for implantable devices such as pacemakers, defibrillators, drug pumps and neurostimulators. The switch includes reed contacts hermetically sealed within a tubular glass envelop, wherein the reed contacts extend through ends of the envelop to provide external contacts. A trilobular cross section mounting bar is attached to each external contact such that the reed switch can be mounted on a mounting surface such as a ceramic substrate or the like. A protective housing contains the reed switch while the attached trilobular bars extend from a side of the housing to allow communication between the switch and the mounting surface. Further, a testing apparatus is provided for evaluating how the housed reed switch will perform when installed in the implantable device and subjected to stray (must not operate) as well as designated (must operate) magnetic fields.