The small CT601 crawler from Cobra Technologies from Trio Vision has been tested to 20 psi with superior traction, with its brass construction making it a hardy performer for its size, without adding undue weight. It can be configured with a powered camera lift and accessory wheels, making the system capable of inspecting 30-inch or larger lines. Conventional wisdom holds that 90 percent of pipe in the ground is 10 inches or smaller, making its size ideal the majority of the time. It can be paired with the Cobra PTZ Version 9 camera, which is rated from 6 to 48 inches. 800/443-3761; www.cobratec.com.