FIG. 1 is a perspective view from above of a seat liner showing my design;

FIG. 2 is another perspective view from above thereof;

FIG. 3 is a back elevation view thereof;

FIG. 4 is a front elevation view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a left side view thereof; and,

FIG. 8 is a right side view thereof.

The dash lines on the seat liner represent conventional stitching. The chair depicted in broken lines is also for illustrative purposes only and forms no part of the claimed design.