Abstract: A workbench of a foldable, portable nature includes a working surface formed by a pair of vise bars. The vise bars are operated by a pair of clamping screws which are so interconnected with a movable one of the bars by connections which allow limited lateral movement of a nut, carried by one of the screws, and the movable vise bar to permit one clamping screw to be rotated at a different speed than the other clamping screw. The vise bars are carried by a supporting structure formed by two frame members, means being provided for retaining the frame members at an acute angle to each other in an erected position of the workbench and for enabling the frame member to lie adjacent each other in substantially parallel planes, when the frames are in a collapsed position of the workbench.