English: NASA astronaut Shane Kimbrough (right) and ESA astronaut Thomas Pesquet (left) inside the Quest airlock during their pre-breathe session prior to a spacewalk. Astronauts breathe 100% oxygen prior to a spacewalk to help purge excess nitrogen from their blood stream and avoid decompression sickness. During the nearly six hour spacewalk, the two astronauts successfully installed three new adapter plates and hooked up electrical connections for three of the six new lithium-ion batteries on the International Space Station. Astronauts were also able to accomplish several get-ahead tasks including stowing padded shields from Node 3 outside of the station to make room inside the airlock and taking photos to document hardware for future spacewalks.