Contact sleeve for plug-and-socket devices

A plug-and-socket device, comprising:

• a plug pin;
• and
• a contact sleeve having a cavity extending in a direction of an insertion axis for receiving the plug pin, said contact sleeve including at least two contact fingers arranged in parallel relationship to one another around the cavity and configured to move elastically apart while expanding the cavity when the plug pin is inserted, at least one of the at least two contact fingers being formed on an inner side in facing relation to the cavity with a plurality of depressions which lie in a contact surface on the inner side and define with the contact surface an edge angle of less than approx. 100°, each depression having a beginning and an end with respect to the direction of an insertion axis, said contact surface representing on the inner side of the contact finger a surface which comes into contact with the plug pin, when the plug pin is inserted, and said contact surface bordering both the end and the beginning of each said depression with respect to the direction of the insertion axis.