Powered by batteries, the APK2 stimulates circulation via alternating internal air bladders. The cushion is designed for consumers who have pressure sores or are at high risk for developing them — and is custom built to offload existing sores while alternating elsewhere. The cushion weighs 3 lbs. and has no size or weight limitations. The battery runs 40 hours per charge, and the APK2 includes low-battery and low- pressure alarms.