STS-118, August 2007
Astronaut Rick Mastracchio, STS-118 mission specialist, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk, Mastracchio and astronaut Dave Williams (out of frame), mission specialist representing the Canadian Space Agency, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.
Reproduced from the NASA Website
AZ Technology produced black and white assembly targets on ISS.