Rotationally locking pins on either side of the element prevents element damage while running in a hole. The MPas contains an elastomeric element with a composite structure set mechanically by applying a hydraulic pressure differential from the packer's inside diameter (ID) to the outside diameter (OD). When the differential pressure is high enough, the lower piston shears and moves down, releasing the piston as hydraulic differential pressure and hydrostatic pressure acting against an atmospheric chamber. The force acting on the setting piston mechanically sets the element. The setting force is locked into the element by a body lock ring so that the element Remains set after the hydraulic force is released. The hydrostatic setting force continues to act on the element so that it will continue to conform to the wellbore even if its geometry changes over the packer's life. This design allows additional hydraulic setting force to be applied to the packer at any time during its life.