Applies to twist-on connecting devices for connecting two or more unprepared rigid and/or flexible copper conductors having a cross-sectional area of 0,5 mm[2] up to and including 16 mm[2] and complying with IEC 60228, the total cross-sectional area of the connected conductors not exceeding 35 mm[2]. It also covers low voltage circuits up to 1000 V a.c. and 1500 V d.c. where electrical energy is utilized for household and similar purposes.