The invention relates to a foot pedal control unit for an ophthalmic surgery system. The unit has a base and a treadle that is configured for pivotal pitch movement and for pivotal yaw movement relative to the base for generating control signals to an ophthalmic surgery system. The unit further comprises an inlay cover that is removably placed on the treadle. Optionally, the unit comprises a locking element that is movable between a lock position wherein the treadle is locked against pivotal yaw movement and a release position wherein the treadle is enabled to perform pivotal yaw movement.