KINESIS Advantage360 Professional Split Ergonomic Keyboard - Bluetooth

Concave keywells  are scooped into a bowl shape to reduce hand and finger extension and relax muscles.
Separating the keywells positions the arms at shoulder-width to keep wrists straight and perpendicular to the home row to reduce abduction and ulnar deviation.
The keys are arranged in vertical columns (rather than staggered) to better reflect the natural motion of your fingers.
The two keywells are tented to moderately raising the thumb side of the hand. Tenting puts you in a more neutral, handshake posture and reduces the stresses caused by forearm pronation. Choose from one of three heights depending on your preferences.
The integrated palm supports reduce stressful bending of the wrists and provide a convenient place to rest your hands when you are not actively typing. Add the new premium pads for even more support (AC360PP Sold Separately).
The thumb clusters include frequently-used keys such as Enter, Space, Backspace, and Delete to  redistribute the workload away from your relatively weaker and overused little fingers to stronger thumbs.
The Advantage360 may look big, but it actually has a smaller footprint than most keyboards because we eliminated the numeric 10-key so you can place the mouse closer to your body, reducing painful over-reach.
Functions keys are located in the number row and accessed via the Fn Key for reduce reach and enhanced portability.
Integrated Tenting: With a press of a button easily switch between 3 tent settings (low, medium, and high) to reduce forearm tension. The low setting replicates the same tenting angle as the original contoured keyboards.
Mechanical Key Switches:   The Advantage360 Professional utilizes the Gateron Brown stem low-force tactile key switches.   Tactility is a slightly elevated force around the midpoint of the stroke of the key which lets you know the switch is about to be activated. A tactile response is preferred by many ergonomists, because it cues your fingers that activation is about to occur and can reduce the frequency of bottoming out the switch with a hard impact.
Programmable: Unlike the base model which uses Kinesis propreitary SmartSet Engine, the Pro uses open souce ZMK firmware. Program the keyboard using the web-based configurator or simple text syntax. Power users can access the code on GitHub to build and share their own features.  
Note: The Advantage360 Professional is designed for power users and is not nearly as easy to program as Advantage360 with SmartSet. ZMK does not support onboard programming so users who rely on that feature may not be satisfied with the Pro.
ZMK Configurator: The Advantage360 Professional GUI leverages an open-source, web-based application designed by Nick Coutsos. Add layers, customize actions, and configure basic macros.