Latch mechanism and system for downhole applications

A system and method for conveying a tool to a target sub within a tubular string having a number of subs. Each sub may include at least one ledge or shoulder in or on its interior surface that can be used as a latch stopper or stopper, for receiving and engagement with a latch. The subs may also have a latch deflector or deflector. In one embodiment, the latch deflector is a latch-deflection shoulder protruding into the internal diameter (ID) of the string for deflecting a latch, to be subsequently introduced, out of or into the latch-stopping shoulder. The distance between the latch stopper and the latch deflector, referred to as the "deflection radius," may be used as an address that uniquely identifies each sub, and can vary from sub to sub.