Elon Musk's spat with caver Vernon Unsworth started last week after rescue teams rejected Musk's offer of a mini-submarine created by his rocket company SpaceX to help rescue a 12-member soccer team and their coach trapped inside a flooded cave.
Xavier Van der Stappen used cardboard donated by a local factory and worked with designers to produce the first 20 portable cardboard tents which he paid for himself. He is planning to make 100 more after he receives feedback from users.