What kind of dog is Fang, Hagrid's dog in the Harry Potter movies?

I need to know what bree Fang from Harry Potter is. I have heard that he is an English Mastiff. I have an English Mastiff puppy, and if that is the same breed, then wow!!!. He is huge. My puppy is almost 5 months and almost 90 lbs and sort of looks like Fang, just not as much black and not quite as wrinkley.