[3] The boat has been an Olympic class since it was selected by the International Sailing Federation to be the men's high performance double handed dinghy Sydney Summer Games of 2000.

Its derivative featuring a re-designed rig, the 49er FX, was selected by World Sailing to be the women's high performance double-hander at the Rio Summer Olympics of 2016.

It incorporates ideas developed in Julian Bethwaite's 18ft Skiffs, notably the Prime Computer series of boats, which were double handers.

The hull is made of Epoxy GRP and foam sandwich laminate with carbon fibre in high load areas.

It includes two solid wings, also called racks, that clip into the side to increase righting moment of the trapezing crew.

The main and jib combined are 20 square metres, fully battened and made of reinforced Mylar (film polyester).

The main was redesigned in 2007 from a full, curved roach plan to having a square on top in order to provide more sail area and to control more shape adjustment.

It consists of a 49er hull, wings, and foils, with a scaled down rig designed to suit the weight of an elite female crew.