The ornamental design for a firegratefret, substantially as shown and described.
FIG. 1 is a side view of a fire grate fret showing my new design;
FIG. 2 is a front elevational view thereof; and
FIG. 3 is a perspective view thereof shown mounted on a fire grate, which
fire grate is shown in broken lines for illustrative purposes only and
forms no part of the claimed design.