I opened the box for the coaster and looked to see what batteries it would take and find the power switch (the button on the bottom gets pressed down when you put your cup on it) before I spotted a spot where a cord would go. I found the cord in the box and plugged it all in, and saw the colors shine through the cup with what I had in there, seeing more than the one color I was expecting, not having inspected too far on the store page. After a while, I unplugged it to move it elsewhere on my desk, only to learn it had internal batteries that could retain the charge from the cord.

Pleasant surprise after pleasant surprise. 13/10

A very cool looking coaster that I've been wanting to get. Plus I'm a sucker for LEDs. Overall it's a great addition to my gaming setup.

Being able to plug it in is neat, and it makes me a unique addition to my desk. Looks like the statue of Vergil is gonna have to go in the trash where it belongs

Pretty cool lighting for the cups battery or plug in is cool to have

Got this for my son for his birthday. He plugged it into his computer and immediately loved it. It goes very well with the RussianBadger shaker cup he bought for himself. Awesome color changing effects, my son is very happy with it.