A miniature pneumatic switch apparatus has a diameter of three-eights inches and a height of five sixteenths inches and operates from minimal pressure to 100 psi. A pressure responsive unit includes outer spaced guide walls extending from a pressure movable wall. A switch unit is secured to the guide walls in spaced aligned relation to the movable wall and forms an operating chamber. A spring carrier is mounted within the chamber. The carrier includes a plate having a lateral opening with a beam spring extending therethrough, with the spring ends supported in openings aligned with the plate. An elastic band encircles the support walls and holds the beam spring in place. The opening in the plate facing the switch unit is a flat face, and the opposite face facing the movable wall is curved for line contact with the spring.