Abstract: A support device for supporting the forearm of a worker in a generally horizontal plane comprising:(a) an attachment member for affixing the support device to a support member;(b) a lower support member having a forward end and a rearward end, the rearward end being pivotally mounted to the attachment member for free pivotal rotation of the forward end of the lower support member within an arc with respect to the attachment member due to force applied to the lower support member when the arm of the worker is moved in the horizontal plane; and,(c) an upper longitudinally extending support member for supporting the forearm of a worker, the upper member having a forward end and a rearward end, the upper support member being slidably mounted on the lower support member for movement of the upper support member in the longitudinal direction between a recessed position and an extended position with respect to the lower support member due to force applied to the upper support member when the arm of the worker is move