4 layer structurendashthe traditional backlit membrane keyboard has only a 3 layer structure ares adds one more layer to enhance the robustness 19 key roll overndashanti ghosting keys capability enables you to press up to 19 keys simultaneously without creating any key conflict all keys lock modendashenabling the all keys lock function you can take a rest and temporarily leave your keyboard unattended this feature alleviates the worry of pressing a wrong key to affect the game play game mo