Wow mugs might sound a bit crazy but on using one of these gems you will say Wow !!. Watch as your mug design vanishes before your eyes these wow mugs have a special coating that is activated with heat. This is great as you can have a plain mug that when the user poors hot tea in your logo will appear before there eyes. Even though there are more expensive than normal promotional mugs if your budget can stretch then this product will guarantee you a great return on investment.