The International 420 Class Dinghy is a double-handed (2 crew) monohull planing dinghy with centreboard, bermuda rig and centre sheeting. The name describes the overall length of the boat in centimetres (the boat is exactly 4.2 metres long). The hull is fibreglass with internal buoyancy tanks. The 420 is equipped with spinnaker and optional trapeze. It has a large sail-area-to-weight ratio, and is designed to plane easily. It can be rigged to be sailed single-handed.