This keyboard is based on the K2 and features a number pad in an incredibly compact and unique 96% layout. Ideal for power users who need to get around well at home, on the road or in the office, the K4 offers wide wireless compatibility for PC, Mac, Linux and Android devices. The K4 comes with Gateron switches, which are considered the smoothest switches on the market right now. Whether for PC, Mac OS, Linux or even Android devices; the Keychron keyboards are compatible and meet all requirements. The desired operating system is set via a switch on the keyboard frame. For improved workflow and multitasking, you can connect up to three Bluetooth devices simultaneously and switch from laptop to tablet or mobile. This Keychron keyboard has a fully hot-swappable PCB, which means that the switches are not soldered in. So you can easily upgrade, swap and mix the switches (without soldering), just plug and unplug as you like. The keyboard is equipped with excellent RGB LED backlighting for an optimal and customised typing experience. With 15 different lighting modes, flashing, breathing or static, the desired atmosphere can be created. This model features a sleek and stylish aluminium frame for increased durability and rigidity. The large 4000 mAh battery lasts up to nine days (8 hours per day up to 72 hours) with the backlight on, or four weeks with the backlight off, and is fully recharged in just three hours.