Citizen Eco-Drive watches harness the power of light, from any natural or artifical light source, and convert it into power for your watch. Light passing through the face of an Eco-Drive watch is collected by a hidden solar reflector and stored in an Energy cell. This means that Citizen Eco-Drive watches never need a battery change. Citizen have placed their Eco-Drive technology in both mens watches and ladies watches. Their well designed range of watches are perfect for any occasions.