Comment by dynendal

I never understood why the K6 had aluminum on the sides, but not the back. For the last few years, I had two K6's with different switches I swapped between. When one keyboard's battery went low, I would swap and keep working while charging.

Then, on my newer K6 the battery turned into what reddit affectionately calls a "spicy pillow." The keys warped convex around the bulged battery and equivalently bulged out the back plastic. That's why you can't put metal back there. I quickly brought it to my nearest battery recycling center. I could've just removed the battery, but I also enjoy having my face in one piece