An improved electrostatic discharge protection guide rail system for a PCB which is capable of providing an electrostatic discharge protection function so that a PCB of a plug-in unit disposed in a sub-rack of an electronic instrument from a damage due to an electrostatic discharge (ESD),...http://www.google.de/patents/US5708552?utm_source=gb-gplus-sharePatent US5708552 - Electrostatic discharge protection guide rail system for printed circuit board 
