This is a 155ft MPO (female) to MPO (female) 12-strand yellow crossover riser-rated fiber patch cable. OS2 is a standard single-mode optical fiber commonly used with wavelengths of 1310nm and 1550nm (9/125 microns), and has a maximum attenuation of 1dB/km. The OS2 standard is defined in ISO/IEC 11801. This plenum cable is the only cable allowed in spaces defined as air plenums, such as raised flooring systems and air handling ducts. Plenum cables must self-extinguish and prevent re-ignition. Our patch cables are 100% compliant for all of your networking needs. Our products are guaranteed by federal law to not affect or void OEM warranties.