Morphing Mugs Harry Potter - Hogwarts Marauder's Map - I Solemnly Swear - 11 oz Heat Sensitive Mug – Image Revealed With HOT Liquid added! - Officially Licensed Collectible

My Potterhead friend loved the gift.

Best mug of Harry Potter and looks pretty cool.

It is a nice product. Seems to be made well.Great idea for any Harry Potter fan.

You can barely see the design when the mug is cold and all black - I mean, yeah, you can see the design if you look for it, but come on - it's not REALLY magic. The water in m Keurig coffee machine is hot enough to make the picture appear. Very cool design - works perfectly. Design goes back to almost all black when the coffee gets cold. Go for it - you and your Potter fan will love it - I would certainly repurchase.

This wasn't the one I thought I was getting. It's on the smaller size for a coffee cup. However make the person I was gifting was happy with it overall. I did notice some of the black wearing off with minimal use.

My wife it and is a fan of Harry Potter

I'm a single father with 2 teenagers, and I bought this mug as a gift for my 13-yr-old daughter, who is a huge Harry Potter fan. She absolutely loved it. Now when she's making tea or hot chocolate, I get a little extra smile and sometimes even a kiss on the cheek and a "I love you Dad" which isn't too common with teenagers these days! By the way, the mug works exactly as it should -- black when cold, visible map when hot. I'd definitely recommend this if you need a gift for your own Harry Potter fan.

Pretty cool transformation. You can see some color variation when cool, but it really does pop when filled with hot liquid. Great gift!