Adults generally do not grow to more than 90-120 cm (3-4 feet) in length, although some specimens have reached 152 cm and even 182 cm (5-6 feet), but this is very rare. The build is stocky while the head is relatively small. The scales are smooth[4] and both sexes have anal spurs on either side of the vent, although males have larger spurs.
The color pattern is typically black with light brown-green side and dorsal blotches. The belly is a white or cream that may or may not include scattered black markings. However, those in the pet industries have, through selective breeding, developed many morphs: genetic mutations with altered colors and patterns.