A torque amplifying knob apparatus is disclosed for engaging a screw associated with an orthopedic exterior fixator. The apparatus has collapsible turn levers. Each lever has a body extending between a movable end and a hinged end. A central screw turn actuator has an outer side and an inner side. The hinged end of each lever is connected via a hinge to the outer side of the actuator. The movable end of each lever is movable between a collapsed position where each lever is situated over the outer side of the actuator and an open position where the movable end is situated outwardly from the outer side of the actuator. The actuator is engaged with the screw so that movement of the actuator is caused in first and second linear directions along the cylindrical threaded body when rotational force is applied in first and second rotational directions, respectively.