Fill ‘er up….with java. The Fuel Gauge Mug has a color changing “fuel” meter on it’s side that changes it’s color to red as you fill it up with a hot beverage. The microwave safe white ceramic mug can hold up to 16 ounces of your fuel of choice. Hot stuff! I can see this mug as a popular “secret Santa” item in your office this year. Yes it’s still October and I just mentioned Christmas shopping- never too early, right?