Unfortunately, these materials can easily flex, especially when pressed in the middle of the keyboard. It allows a users to quickly and easily adjust per-key backlighting, switch lighting modes, and even record macros with just a few key presses.

During use, there was a very small perception of lag, but this is one of the issues with Bluetooth protocols in general.If you accidentally press the lever or decide not to remove it, place your thumbs on the left and right side of the keyboard top plate and gently rock it side to side to lock it back into place. If the item comes direct from a manufacturer, it may be delivered in non-retail packaging, such as a plain or unprinted box or plastic bag. The CK721 LED brightness is decent in dark and medium-low light environments and appears quite faded in medium-high to high light environments. These two factors make the CK721 feel a bit less premium despite its good appearances and material choices. They go against the CK721’s high build quality with tons of stem wobble, and we found them to be pretty noisy, too.

Simply holding down the FN key and pressing the corresponding side-printed secondary functions key will allow you to adjust brightness, volume, skip audio tracks, RGB backlighting, etc. The legends on the Cooler Master CK721 with its north-facing LEDs resulted in generally bright keys illuminated for their primary functions.

I didn’t have any issues using this keyboard with various mobile phones like the Apple iPhone 13 Pro, Google Pixel 6 Pro, and the Samsung Galaxy S21 Ultra.