Adjustable armrest of a mobile work machine, in particular an industrial truck

The adjustable arm rest has a guiding device (10), two carrier bodies (3,4) and a shaft guidance (21a,21b), which has a guiding rod (25a,25b). The guiding rod is arranged in a guiding retainer (26a,26b) in lengthwise-adjustable manner. A flat wed guidance (22b) is formed by sections of an adjusting device (2), particularly by sections of the carrier bodies.