The present invention is a system and method for fastening a second object to a first object that resists unfastening, for example due to vibration or disturbance, until unlocked. The locking system essentially comprises: a girder having one end anchored to the first object, and another end having an externally threaded terminus also defining an internally counter-threaded axial bore; a cap having an essentially planar outer face, an internally threaded transplanar bore for rotational engagement with the terminus of the girder, and a pair of domed arches on opposite sides of the transplanar bore extending from the circumference of the transplanar bore toward the periphery of the cap; and a counter-threaded bolt having a diameter smaller than the transplanar bore, a length sufficient to rotationally engage the axial bore of the girder while inserted through the transplanar bore, and a head having a pin-aperture; a pin inserted through the pin-aperture cooperating with the domed arches to prevent substantial rotation of the cap engaged with the girder terminus and the bolt engaged with the girder axial bore. The system also includes a tightening tool for tightening the cap.