"Dryhead Slim's" rattle. "Dryhead Slim" is the name of this 'watch rattler' (can't always have a watch dog, can you?) on the Tecomate Ranch in Starr County, Texas. He is a Texas Diamondback Rattlesnake about 5-6 feet long. (a little less than 2 meters) and about 3-4" in diameter. He was about 4 years old (has 12 rattle segments in his rattle) when this picture was taken, and keeps rats and other small vermin (as well as unwelcome visitors) away from the ranch house.