Lightweight Ergonomic Inflatable Cushion

38 cm square footprint, 8 cm seated height, 280 g total weight. Manufactured using commercial-grade PVC with welded seam integrity and a leak-tested inflation valve. Serves dual roles: primary seat padding and secondary lumbar/back support attachment. Air chamber layout distributes weight evenly across ischial tuberosities while elevating sacrum and L4–L5 vertebrae — reducing intervertebral disc compression observed during prolonged static sitting. Air retention exceeds 72 hours under normal UK room temperature (18–22°C) conditions. Designed for multi-environment use: enhances dining chair comfort at home, improves posture on budget office chairs lacking built-in lumbar adjustment, and delivers reliable support in vehicles or temporary outdoor settings — all without tools, assembly, or power source.