ZPA Subminiature SMT Snap-Acting Switches C&K Switches ZPA Subminiature Surface-Mount (SMT) Snap-Acting Switches are compact single-pole, single-throw (SPST) switches designed for low-current 0.1A signaling applications. The ZPA series features a reliable snap-acting mechanism and plunger or lever variants with 80g or 150g operating force. The switches deliver a long electrical and mechanical life with 1M cycles each and operate in a –40°C to +85°C temperature range. C&K Switches ZPA Subminiature SMT Snap-Acting Switches are ideal for communication devices, security / alarm systems, consumer electronics, and more.