A marker-holder system for an electrical terminal block comprising a longitudinal marker-holder device according to a direction of extension, the marker-holder device comprising a central part with a thinned portion and a first end in the direction of extension and a second end in the direction opposite to the direction of extension, the system comprising a first fastener configured to be disposed on the terminal block, the first end and/or the second end being configured to cooperate with the first fastener in a removable manner, the thinned portion being divisible.