 The new stations featured a longer design life and a second docking port at the aft of the stations – crew exchanges and station "handovers" were now made possible by docking two crewed Soyuz spacecraft at the same time.Furthermore, the uncrewed Progress resupply craft was created based on the crewed Soyuz, to resupply the crew and station with air, air regenerators, water, food, clothing, bedding, mail, propellants, pressurant, and other supplies.While the Progress docked to the station's second docking port, the crew's Soyuz spacecraft could remain docked to the station's first port.