RAFI RF19 Short-Travel Keyswitches C&K Switches RAFI RF19 Short-Travel Keyswitches feature a large actuation area, making them ideal for use in low-profile keyboards. When designing low-profile keyboards with a grid of >,= 23mm, frame webs remain free between the individual keys. The overlay can be glued onto these frame webs. It is recommended that area embossing is used over the keys for the overlay.