This is a type of sailing dinghy which is sailed by two people. This particular boat comes in three forms. The International 420, the Club 420 and the Collegiate 420. The first is dead in the U.S. While the latter two are used exclusively in the U.S. The specifications for all of them are:
The basic differences are:
The International is the original. It is the lightest hull and was designed for performance and to be a trainer for the Olympic 470 class.
The Club came next. It made the hull heavier to give better durability. An untapered mast was also added to lower costs.
The Collegiate was adopted from the Club for use in college sailing. It is the same as the Club except for the fact that the trapeze and spinnaker were removed. This along with the FJ and Laser are the primary boats used in ICSA competitions.
The 420 is an excellent trainer for sailors aged 13-18 and is well established in junior sailing programs across the U.S. It serve as a good introduction to double-handed sailing as well as basic sail tuning.