Case material: stainless steel Stainless steel 316L (Stainless Steel) is a very durable material that theoretically can not be destroyed. It is hard (non-bendable and non-crackable), color stable, antiallergic (does not react with body fluids and therefore no metal components are not released into the skin and flesh) and has anticorrosive surface (the surface is resistant to oxidation and corrosion. Moreover, it is also resistant to fresh and salt water). Movement: battery The watch is powered by a battery.