A mechanism for dual-height tables, counters, or the like, in which the top lifts and pivots upward and outward on pairs of links attached to the top and to link housings attached to the table or counter base. Each pair of links comprises a pivot link and a locking link. The pivot link has holes at each end which ride on pins or the like attached to a bracket on the top and the pivot link housing on the bottom. The locking link is similarly arranged at the top, with a hole for a pin attached to a bracket. The bottom end of the locking link has an elongated slot, through which a pin is inserted to fasten the locking link to the locking link housing. When the top is in the lowered position, the pin is in the end of the slot closest to the end of the locking link. As the top is raised, both links pivot on the pins in the link housings. When the top has reached its most-forward pivot position, the locking link rests on a forward stop. The locking link is then slid downward into a locking pocket in its housing, the pin moving upward in the slot until it rests on the top of the slot and the top of the table is horizontal. At this point the top is rigidly supported and locked in the forward/upward position.