No batteries required, zero running costs. Safe design that automatically reacts to sound an alarm without worrying about running out of battery. Gentle sitting for users. Gentle sitting. The stain-free seat combined with the urethane memory foam provides a soft sitting experience. Good assistance tool for caregivers This is a reliable nursing partner that will alert you to get up even if you have left your eyes from nursery. Size (H x W x D): 15.4 x 15.4 x 2.0 inches (39 x 39 x 5 cm); Weight: 25.6 oz (700 g); Material: Cover: Vinyl leather, Cushion: Memory foam + urethane foam.