The 311SM3-T Honeywell Snap Action Switch is a sub-miniature basic switch used for simple or precision on/off application needs. It comes with a long operating life, elongated mounting hole for easier, more accurate mounting and choice of actuation, plunger, as well as a variety of integral and auxiliary actuators. This Single Pole Double Throw Switch is light weight and small in size.</p> <p>A Snap Action Switch is a type of momentary contact micro switch which operates at rapid speed as it takes very little force or stimulus to operate. The SM Series switches are slightly larger than the SX Series switches. These highly sensitive switches are very often used in computer/business equipment, test instruments, medical/dental equipment, communications equipment, HVAC equipment, manually operated devices and valves.</p>