American Staffordshire Terrier

The American Staffordshire Terrier also known as Amstaff is a medium-sized, short-coated American dog breed. It is one of several breeds commonly known as pit bulls. In the early part of the twentieth century the breed gained social stature and was accepted by the American Kennel Club as the American Staffordshire Terrier in 1936. The name was changed to reflect difference from theStaffordshire Bull Terrier of England.

Weight	40-60 lbs.
Height	17 to 19 in (43 to 48 cm)
Coat	Smooth
Color	Any color, solid, parti, or patched is permissible, but all white, more than 80 per cent white, black and tan, and liver not to be encouraged.

source : wikipedia