The crews of the ISS are ferried to and from Earth by Russian Soyuz spacecraft and US space shuttles. The space shuttle orbiters are the largest, measuring 37.23 m long by 23.79 m wide and 17.86 m high. While the Soyuz craft remain docked for months at a time, and act as lifeboats, the shuttle only stays docked with the ISS for a matter of days. The longest a shuttle has been docked to ISS was 11 days 20 hours and 36 minutes, by the STS-123 mission of Endeavour, which delivered the Kibo module and the Dextre robot to the ISS.