Service Module
During the station's assembly, the Russian-built Service Module will provide living quarters for a permanent crew of three, who will be able to look out no less than 14 windows. The 43-foot-long, 42,000-pound module will also contain systems for life support, data processing, propulsion, and guidance.

Service Module At the Krunichev Space Center in Moscow, technicians work on the Service Module in 1997.