The MASTIFF is among the Working Group! 

For the uninitiated, a face-to-face encounter with these black-masked giants can be startling. Standing as high as 30 inches at the shoulder and outweighing many a full-grown man, Mastiffs make an immediate and lasting impression. The rectangular body is deep and thickly muscled, covered by a short double coat of fawn, apricot, or brindle-stripe. The head is massive (a word that comes up often with this breed), and a wrinkled forehead accentuates an alert, kindly expression.

Personality: Courageous and dignified, but good-natured and docile 
Energy Level: Somewhat Active; An adult Mastiff is content with long walks and a good romp 
Good with Children: Yes 
Good with other Dogs: With Supervision 
Shedding: Seasonal 
Grooming: Occasional 
Trainability: Responds Well 
Height: 30 inches & up (male), 27.5 inches & up (female) 
Weight: 160-230 pounds (male), 120-180 pounds (female) 
Life Expectancy: 8-12 years 
Barking Level: Barks When Necessary