A coxed four, abbreviated as a 4+, is a racing shell used in the sport of competitive rowing.
It is designed for four persons who propel the boat with sweep oars and is steered by a coxswain.
With a bowloader, amplification is needed to communicate with the crew which is sitting behind, but the cox has a better view of the course and the weight distribution may help the boat go faster.
Racing boats (often called "shells") are long, narrow, and broadly semi-circular in cross-section in order to reduce drag to a minimum.
However most rowing clubs cannot afford to have a dedicated large hull with four seats which might be rarely used and instead generally opt for versatility in their fleet by using stronger shells which can be rigged for either as fours or quads.