In Southern California, nearly 10,000 of those boxes were attached to wheeled trailers known as chassis that were needed by truckers to move other companies’ goods on and off port docks. In the midst of the busy preholiday shipping season, the shortage of chassis placed strain on supply chains up and down the West Coast.According to MANA, The Port of Long Beach and Total Terminals International LLC—which runs port terminals for Hanjin, including its Southern California operation in Long Beach—have arranged for a container ship to remove 4,300 containers that have been sitting in container yards and warehouse lots since the bankruptcy filing.