Abstract: A cushion for seats, wheelchairs, mattresses, etc. is disclosed. The cushion includes fluid-filled cells. Each cell is in fluid communication with adjacent cells via conduits. Constrictures such as check-valves and duckbill valves may be located inside the conduits to restrict or otherwise regulate fluid flow into or out of a particular cell. A control pin may be used to selectively enable or disable said constrictures. In this way, the cushion may be customized on a cell-by-cell basis, providing a cushion that can be tailored to the individual needs of the patient.