Extreme-duty 99-840 finger stock is an EMI shielding gasket engineered for large enclosures that have significant gap fluctuations between mating surfaces. Low compression force. Said to provide deflection range of 0.25" (6.4 mm) and installs on most enclosure panels with a clip-on lance. Optional “C” style retaining lance is available. Can be ordered in 10 surface finish and plating options.