Abstract: A clew constructed from carbon fiber composite is provided for a sailboard boom, the clew having a pair of cylinders having longitudinal axes and connected together by a trapezoidal central flange having substantially equal non-parallel sides connected to the cylinders parallel to their axes to secure them in a predetermined relative angle. The crew further includes holes through the central flange and notches in the rear edge of the flange for attachment of a lanyard or tie line rope that loops through the holes, around sheaves on the sail and through the notches which secure the end of the lanyard while permitting it to quickly be released for adjustment of sail trim. The clew further comprises a spring pin slot transverse each cylinder that interfaces with a an aft spring pin in a telescoping adjustment tube, the slot facilitating adjustment of the tube within the arm of the boom because the slot allows rotation of the tube without removal from the clew.