Multi-colour set is a set of wrenches in different colours that enables the user to identify wrench sizes by colour, while Single-colour set is a set of wrenches in a same one colour that can differentiate particular production line or worker. Single-colour sets are available in 6 colours and both Multi-colour set and Single-colour metric sets are available as a set of 7 pcs. and 9 pcs. In addition, silk-screen printing is applied to wreche sizes from 2.5 mm to 10 mm (1/8″ to 3/8″.)