B3FS-4 SMD Tactile Switch Omron Electronics B3FS-4 SMD Tactile Switch features distinctive snapping action and extended mechanical/electrical durability. Omron Electronics' B3FS-4 SMD Tactile Switch is 12mm x 12mm with a height of 4.2mm and is packaged with embossed taping for automatic mounting. Series now includes high-force and projected plunger options.