Glass cotton lap felt covering the insulation cotton nail, stick outward, make insulation cotton nail penetrate cotton and stick a face, with insulation button nailing pad will glass cotton and duct fixed together.
For corporations, the sport is the latest in a series of teamwork-building fads that began with Outward Bound trips in the 1970s and continued with pugil-stick battles and obstacle courses in the 1980s and 1990s.