materials: Constructed from 3D breathable mesh and a soft sponge head pillow, paired with a lightweight yet durable aluminum alloy brace for support. Adjustable design: The backrest can be easily mounted or disassembled, ensuring a fit for your travel chair. User friendly convenience: The headrest can be simply removed when not in use or for folding the wheelchair for easy storage. Compatibility note: Please verify that the width of the wheelchair armrests is suitable for installing the fixed clamp, approximately 14 inches. This product is compatible with wheelchairs measuring 16 to 20 inches in width (wheelchair not included). Benefits at a glance: improves back support and neck comfort during extended sitting; lightweight frame adds minimal extra weight; easy to install and adjust for a fit. Use scenarios: Travel: on planes or long road trips, provides stable back support and can be removed to simplify packing for storage. Public venues or rental chairs: quick installation on chairs 1620 inches wide for consistent posture support. Home or work: extended seating at desk or couch to reduce fatigue, with headrest removable for compact storage.