This is a 1000ft non-terminated yellow OFNR (Riser-rated) 2-strand duplex fiber patch cable. OS2 is a standard single-mode optical fiber commonly used with wavelengths 1310nm and 1550nm (size 9/125 microns), and has a maximum attenuation of 0.4dB/km. The OS2 standard is defined in ISO/IEC 24702. 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.