Diesel's mom says: "Diesel" is a nine week old Bull mastiff. He is eight and nine weeks old in the photos. He was born in Nebraska, but now happily resides in Colorado. He was a Christmas gift from my husband, who has claimed Diesel as his very own. So much for MY Christmas gift! We are more than thrilled with this beautiful puppy. He is very intelligent and stubborn. Playful, yet lazy. For our family, he's absolutely perfect!!!!!