the danger of premature shearing of the screws is minimal in operation when there is no pressure differential between the tubing and the annulus spring 60 is at its free or unloaded length the holding collar 90 is disengaged with collet fingers 40 after the packer is set and slips 10 are engaged the tensile force and hydrostatic forces induced by pressure below from pressure downward for a horizontal completion will be loaded on the shear screws if the screw protection mechanism is not in place when the pressure below reaches some threshold value in applications like gravel packing frac packing etc the combined tensile force may be large enough to shear the shear screws undesirably in the embodiment shown in fig1 3 when the pressure below reaches some value sufficient to overcome the spring force which is smaller than the threshold value to shear the screws the holding collar 90 will be shifted towards the collet fingers 40 to contact and lock the collet fingers 40 into a groove in the bottom mandrel 100 after the collet fingers 40 are locked into the groove the tensile force will go from the mandrel 120 bottom mandrel 100 gage ring 110 lower cone 20 to the anchors 10 the load path is taken around from the shear screws 30 so they are protected from the shear load when desirable.