Adjustable crossbar for article carrier

An article carrier comprising:

• a pair of spaced, adjacent longitudinal rails;
• at least one crossbar having an elongated rail and at least one slider linearly displaceable along said elongated rail of said crossbar, said slider having an end for removable disengagement with said longitudinal rail;
• a guide for slidably carrying said at least one slider along a portion of said elongated rail;
• a latch carried by each said slider for fixedly locating the position of said slider along said elongated rail;
• and
• a lock for selectively locking said latch in the fixedly locating position,
• wherein at least one longitudinal rail includes a track and wherein said slider includes a track follower, wherein said track comprises a channel, wherein said channel has a restricted opening, and said end includes a first protrusion entrained in said channel,
• wherein said restricted opening has a plurality of spaced recesses, and said end includes a second protrusion shaped for confinement in each of said recesses in a first position to prevent movement of the crossbar in a longitudinal direction of the rails, and wherein said second protrusion is aligned with said first protrusion in a linear direction perpendicular to said opening said end is movable between said first and a second position in said direction, for restricting extraction of said first protrusion on said end from said channel while said end is displaceable to said first and said second positions in said perpendicular direction, and said crossbar is displaceable along said longitudinal rail with said end in said second position.