The ornamental design for a ceiling fan blade irons unit, as shown and described.
FIG. 1 is a bottom plan view of the ceiling fan blade iron unit in accordance with my design;
FIG. 2 is a front elevation view of the ceiling fan blade irons unit in accordance with my design, the rear and side views being substantially identical to that shown; and,
FIG. 3 is a top plan view of the ceiling fan blade iron unit in accordance with my design.
The broken line showing of environmental structure in FIGS. 1-3 is for illustrative purposes only and forms no part of the claimed design.