Container ship sub-classes

Container ships are grouped by capacity in TEU and by the waterway that caps their beam. Feeder and feedermax ships of up to about 3,000 TEU distribute boxes from hub ports; Panamax ships up to about 5,100 TEU fitted the original Panama Canal locks; the New-Panamax or Neopanamax class of about 14,000 TEU fits the locks opened in 2016; and Ultra Large Container Vessels above about 14,500 TEU, now reaching almost 24,000 TEU, serve the main east-west trades and call only at deepwater hub ports. Cell guides in the holds locate and secure the stacks.