J.F. Knudtzen MDH2002 is an empty holder for MD-02 cable markers on red carrier pins, fitting cable diameters of 1.7-2.8 mm and conductor cross-sections of 0.5-1.5 mm². The holder receives user-printed characters so wires can be identified without pre-printed inventory. It is intended for wire numbering in control-cabinet and machine-room wiring. Supplied in packs of ten; typical application is bespoke wire identification during panel building.