On November 22, 2006 Tyurin performed his fourth career spacewalk starting at 23:17 UTC. The spacewalk had been delayed from its scheduled 20:00 UTC start time due to a cooling issue in Tyurin's suit. Tyurin got out of the suit and straightened a suspect hose which apparently had become kinked. During the spacewalk, Tyurin hit a golf ball from the exterior of the "Pirs" airlock. This "experiment" was sponsored by a Toronto-based commercial company, "Element 21", which manufactures golf clubs made of scandium. The ball weighs just 3 grams, compared with 48 grams for a standard golf ball. At that weight, it was unlikely to damage any station components which might accidentally have been hit. The two spacewalkers next task was to inspect a Kurs antenna on the Progress M-58 spacecraft that had docked on October 26, 2006. Tyurin and Lopez-Alegria moved to the rear of the "Zvezda" module and photographed the antenna. Since it was still fully extended, Tyurin used a screwdriver to release a latch and tried to retract the antenna. Russian flight controllers also tried to retract it by activating a motor. Neither succeeded, and the task was abandoned. Next they relocated a WAL antenna, that was to guide the unpiloted European cargo carrier, the Automated Transfer Vehicle, to dock with the station. The two spacewalkers also installed a BTN neutron experiment, which characterizes charged and neutral particles in low Earth orbit. Two thermal covers from the BTN were jettisoned before Tyurin and Lopez-Alegria returned to the "Pirs" airlock at 04:55 UTC on 23 November. The spacewalk lasted 5 hours and 38 minutes.