With Eco-Drive technology, it is powered by light and never needs a battery, so you'll never need to open your caseback or compromise your dive again. Featured in a grey ion-plated stainless steel case with stainless steel bracelet, grey aluminum bezel and matching grey dial, one-way rotating elapsed time and WR200. Featuring our Eco-Drive technology – powered by light, any light. Never needs a battery. Caliber number E168.