Mud river double seat cover's the best - Mud River Two Barrel Double Seat Cover

I have a Jeep Grand Cherokee, and it well covers my back seat. Unlike older models, the closures around the headrests are adjustable--not just in length, but with multiple loops to place the straps through to accommodate different headrest widths.Drawback: Older Mud River covers had more padding.

Overall, these covers are rugged, waterproofs, and they are weighty enough to stay in place.