The latest Robonaut version, R2, was delivered to the International Space Station (ISS) by STS-133 in February 2011. The first US-built robot on the ISS, R2 is a robotic torso designed to assist with crew EVAs and can hold tools used by the crew. However, Robonaut 2 does not have adequate protection needed to exist outside the space station and enhancements and modifications would be required to allow it to move around the station's interior. NASA states "Robonauts are essential to NASA's future as we go beyond low Earth orbit", and R2 will provide performance data about how a robot may work side-by-side with astronauts.