Specification: Color: Black.  Material: ABS.  Switch: RK Brown Switch, Red Switch, Blue Switch (Note: RK71 have many versions with different brand switch, and this product link sells the RK switch version.).  Connection: Bluetooth 5.0 + USB Wired Dual Mode.  Layout: 71 Keys 70% Keyboard Layout.  Backlit:  Blue Backlit.  Dimension: 330mm x 102mm x 37mm.  Polling Rate: 1000Hz.     Features: 1. Bluetooth and USB cable Dual-connection mode: RK71 mechanical keyboard can connect up to 5 devices simultaneously and can switch among them easily. This keyboard is Compatible with most operating systems, including Windows XP/Vista/7/8/10, iOS, for MacOS, Linux and Android.Also, comes with a detachable USB cable, you can easily charge the keyboard while shifting to the wired mode.  2. 71 Keys red Swith: Ambidextrous Shape with Maneuverable Simplicity: Compact minimalistic layout with 71 keys makes you a neat desktop, even folks have nothing to do with Minimalist will dive into its tiny practical design. Tips you might want to know is that keyboard without numpad is most FPS gamers’ choice, more spaces left for mouse movements.  3. For MAC OS and Windows: Function Keys and Shortcut Keys are design for MacOS and Windows, such as applications switch, brightness adjust and so on.  4. Cool Backlight design: Even if RK71 Backlight has no multicolored RGB but only single LED backlit, the 17 dynamic backlit modes keep the plain effect away. Use FN + HOME to choose your ideal mode, adjust the brightness and glowing speed freely. Get some lights on to take your blues away and make your day.  5. Eegonomic design: RK71 Mechanical Keyboard is your good choose in office or home even if in game. Not only it is over-engineered and built to take a beating, it also has great ergonomics and a space saving design delivering a pure, fluid gaming experience. No matter how long you type or how intense your gaming marathons, you are always comfortable.     Package Included: 1 * Royal Kludge RK71 Mechanical Keyboard