TUBULO II is a climbing inspection robot with for inner inspection of boiler tubes. Its locomotion principle is the inchworm type. The adhesion is realized with Magnetic Switchable Device . The inner is able to operate within a tube of inner bore diameter of 25 mm or 1 inch. The robot is modular. The robot and locomotion principle are robust and withstand the harsh environment of corroded boiler tubes. The construction is resistant to water and ferromagnetic particles that separate from the wall. The robot achieves a mean speed of 18 cm/min.