This International Standard specifies the electrical and mechanical characteristics of concentric lay stranded overhead electrical conductors, containing one or more selfsupporting aluminium or aluminium alloy layer(s) as depicted in Figure 1, made of combinations of any of the following metal wires:a) hard-drawn aluminium as per IEC 60889, designated A1;b) aluminium alloy type A or B as per IEC 60104, designated A2 or A3;c) thermal resistant aluminium alloy type as per IEC 62004, designated AT1, AT2, AT3 or AT4;d) regular strength steel as per IEC 60888, designated S1A or S1B;e) high strength steel as per IEC 60888, designated S2A or S2B;f) extra-high stre