The proto-pack is one of the inventions of Baldino. It is, as he describes it, "a small reactor that harnesses onto your back and allows you to fly about". The development of the device has casued a great explotion which made a big hole in his house.Twinsen meets Baldino in his house in Proxima Island, and helps him finish the proto-pack by getting him a hair dryer, which has a component that he needs: a rheostat. Baldino, in turn, pays 10 kashes to Twinsen to test his invention.
The proto-pack helps Twinsen go through the Maritime Museum without touching the wooden floor, which has sensors that activate the alarm. That way Twinsen can get the pirate flag and the ancestral key.
"Proto-Pack. It is controlled with the arrow keys."baggage claim at Citadel Island. Twinsen can go get the proto-pack himself, or pay 102 kashes to Carlo for getting it for him.