A tube of elastomeric material for an air conditioning system or for other system which is on-board of a motor-vehicle is intended to be fitted over a metal connecting element and to be locked onto the latter by means of a crimping operation that envisages the clamping around the tube of a metal clamping element. The tube includes at least one body made of polymeric elastomeric material supplemented with carbon-based nanofillers wherein an outer surface with one or more piezo-resistive areas is provided, where the polymeric material supplemented with carbon-based nanofillers has been made locally piezo-resistive by means of laser irradiation. The piezo-resistive areas arranged on the body of polymeric elastomeric material of the tube can be used for verifying the correct execution of the crimping operation.