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. This HM series hermetically sealed basic switches contain a gas-tight seal which is maintained to transmit force and motion to the switch mechanism through a metal diaphragm. These highly sensitive switches are very often used in adverse gas or vapor environments, oil drilling installations, marine environments, submarines and stationary undersea equipment, refrigeration units, aircraft and spacecraft, earth moving machinery, desert vehicles and cement mills.

11HM1 Snap Action Switch from Honeywell offers N.O./N.C. switch configuration with an operating force of 1.95 N and an operating temperature ranging between -65 °C to 260 °C.