The Mistral TakeOff sail (made by Gaastra) came with the 1982 Mistral TakeOff sailboard. The boom length is 2.6m (long by todays standards). The sail is a soft pin head sail (with a single batten in the top).

The sail is as iconic as the board, but in no way comparable to the fully battened sails that came along only 3-4 years later with their stable design, superior areodynamics and short booms (typically 1.8m or less for a sail of this size)