The ultimate bi-foam cushion that provides pressure relief, redistribution, comfort, and support with an added wedged firm foundation that levels all wheelchair seat surfaces and helps maintain a 90 degree neutral base. Firm foundation eliminates pressure caused by sling-seat hammocking. High-density foam increases comfort and stability. Contoured base rests below seat frame so user sits lower in chair. Provided with a Low-Shear I stretch, launderable outer cover that reduces skin damaging friction. Incontinent-proof, vinyl cover prevents urine from entering the cushion.