1 Use of digits and letters on telephone
sets
2
Rotary dials
3
Pushbuttons or keys
3.1 Ten pushbuttons
3.2 12 pushbuttons
3.3 Dual mode and engraving
3.4 Design of symbols
3.5 Use of colours
3.6 Position of figures, letters and symbols on push-button sets
4
Additional pushbuttons for use on telephones
4.1 General
4.2 Specific
recommendations
Reference