Like @Turtle3D, I don't like the g-keys on a keyboard. I use the bottom left key as a mental placement of where my keyboard is... the addition of g-keys to the g613 screws with my mental note of where the other keys are, because my palm hits them and throw me off.
However, Turtle3D's version of these covers requires you to desolder the existing keys. I didn't want to do that and violate my warranty. My version adds small "hooks" to the cover to let it snap in without having to desolder any keys. Yes, the cover will stick out an extra 1mm because of it; but I'm okay with that.
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