These polarization-maintaining fiber optic patch cables are terminated on both ends with narrow key, ceramic-ferrule FC/APC connectors. Coherent optical technology and G. E fibre: a high-performance, sustainable networking solution. Sumitomo Electric Industries, Ltd. E were introduced and have been extensively deployed worldwide. Available from stock, these cables feature a high-quality polish, which leads to a typical return loss of 60 dB. This Recommendation describes the geometrical, mechanical and transmission attributes of a single mode optical fibre and cable which has the zero-dispersion wavelength around 1300 nm wavelength and which is loss-minimized and cut-off wavelength shifted at around the 1550 nm wavelength region.