A passive method for exploring a region below the surface of the earth. An embodiment of the invention is directed towards a stability unit used with nozzles of a gas liquid contactor andor an enhancer for stable jet formation, and more particularly to reducing the stability of liquid jets formed from nozzles of the gas liquid contactor. Four factory axle mounts on the stock axle may be used for many retrofit applications. Each power switching circuit is responsive to its enable signal being set to connect the voltage source to the at least one voltage line of the associated circuit portion. The bracket has features that facilitate mounting the bracket to different types of structures such as poles, strands, or to hand-holes.