Some embodiments relate to a catheter system having a changeable or adjustable working length. A mapping tool is provided that aids in the configuring of various components of a communications environment, such as an inputoutput subsystem of the environment. The ratchet element is confined inside the main structure, with the capability to move slight along the axis of the handle, and has a protruding tooth for protruding and engaging. 5 nm or over and less than 10 nm.