Both the reed sensor and the Hall sensor are activated by an external magnetic field; however, electromechanical sensors require a mechanical movement that presses into a mechanical lever mounted external to the sensor. This lever will directly close a set of contacts usually internal to the sensor packaging. The sensor can have two or more leads exiting the packaging for direct load switching. These sensors can have single pole single throw (spst), single pole double throw (spdt), and double pole double throw (dpdt) lead configurations.