Citizen Eco-Drive technology harnesses the power of light from any natural or artificial light source and converts it into energy which is stored in a rechargeable lithium-ion cell. It recharges continuously in any kind of light to run forever. Caliber J810 Japanese Quartz Movement - Power Reserve 8 Months - Day/Date. 40mm x 10.5mm Brushed 316L Stainless Steel Case - Scratch Resistant Sapphire Crystal - Screw Down Crown - Solid Caseback. Black Dial - Rose Gold Applied Hands and Hour Indexes - Date Window at 6 O'Clock. 22mm Lug Width Black Leather Strap with 316L Stainless Steel Pin Buckle. Water Resistant to 100 Meters 10ATM. The Watch comes with the Correct Retail Packaging