The Beaufort is a substantial GRP

Glass-reinforced plastic

Fiberglass , is a fiber reinforced polymer made of a plastic matrix reinforced by fine fibers of glass. It is also known as GFK ....

 sailing dinghy, with round bilges (appearing similar to a carvel

Carvel (boat building)

In boat building, carvel built or carvel planking is a method of constructing wooden boats and tall ships by fixing planks to a frame so that the planks butt up against each other, edge to edge, gaining support from the frame and forming a smooth hull...

 smooth hull, a mainsail and a jib.

It was designed by Ian Proctor

Ian Proctor

Ian Douglas Ben Proctor, FRSA, known as Ian Proctor, was a prolific designer of both sailing dinghies and cruisers...

 circa 1965. It's a relatively stable cruising dinghy, and is equipped with a metal centreplate.

The Beaufort sail mark is a trumpet

Trumpet

The trumpet is the musical instrument with the highest register in the brass family. Trumpets are among the oldest musical instruments, dating back to at least 1500 BCE. They are played by blowing air through closed lips, producing a "buzzing" sound which starts a standing wave vibration in the air...

with a black square beneath and a white "B" within the black square.