The K2-6639SP-J3SC-04 is an SMD (surface mount device) tactile switch manufactured by HRO Parts. It is rated for 6mm, 8.5mm, 50mA, 6mm, 100MO, 1000000, 12V, 180gf@±30gf. The operating temperature range is from -25? to +85? and it conforms to ROHS (Restriction of Harmful Substances) standards. This switch is a brick nogging style switch, which means it has a 6mm body with two lobes or “bricks” on the end which can plastic nogging. The switch also has a short operating life of 1000000 cycles.