This part of IEC 61076 covers 10-way shielded free and fixed rectangular connectors for data transmission with frequencies up to 500 MHz and specifies the common dimensions, mechanical, electrical and transmission characteristics and environmental requirements as well as test specifications respectively. Connectors covered in this standard are provided in three codings that differ only for the position of the polarization key and keyway, in view of their differently intended use: " Connectors type A and C are intended for 10/100 Mbit/s as well as for 1/ 2,5 / 5 /10 Gbit/s Ethernet communication. " Connectors type B are intended for all other non Ethernet applications like signalling, serial or other industrial bus communication systems. A-coding: The 45° cut corner used as polarization key and keyway system is located on the lower left corner of the male fixed connector (viewed from mating face). (Figures 5a, 5b) B-coding: The 45° cut corner is located on the upper left corner of the male fixed connector (Figures 5c, 5d) C-coding: There are two 45° corners located at the upper left and lower left corner (Figures 5e, 5f) Subsequently within this document the three codings, A, B, and C will be designated as Type A , Type B and Type C .