The ornamental design for fire pit system, as shown and described.
FIG. 1 is a perspective view of a fire pit system showing my new design;
FIG. 2 is a side view thereof as viewed from the left-hand side of the fire pit system shown in FIG. 1;
FIG. 3 is a side view thereof as viewed from the right-hand side of the fire pit system shown in FIG. 1;
FIG. 4 is a frontal view of the fire pit system shown in FIG. 1;
FIG. 5 is a rear view of the fire pit system shown in FIG. 1;
FIG. 6 is a top view thereof; and,
FIG. 7 is a perspective view of the fire pit system shown in FIG. 1 showing various accessories that may be used in fire pit system.
The evenly broken lines in the figure drawings represent unclaimed environment only and form no part of the claimed design. The dash-dot broken lines represent the boundaries and form no part of the claimed design.