Abstract: Diverse values of a characteristic of rod-shaped articles, such as circumference dimensions, are stored in a signal-addressable memory connected in read-out manner to display units. An article to be examined is disposed in a pressurized conduit and back pressure from the conduit is sensed and a corresponding output signal is generated. The output signal is converted in a further signal having address indication in predetermined relation to the sensed back pressure indication and identifying the memory location storing corresponding article characteristic value information, whereupon the memory energizes the display unit. This practice is preferably implemented by use of an analog-to-digital converter to affect such predetermined relation between the output signal and such address-indicating further signal.