This Sea-Gull Ocean Series dive watch is built around the ST2130 automatic movement with 28 jewels and a 28,800 vph frequency, so it runs without a battery and keeps time through the motion of your wrist. The 44mm round case and matching bracelet are both made from 316L stainless steel, while the crystal and bezel use synthetic sapphire for scratch resistance. With 30 bar of water resistance, it is made for diving and swimming, and the luminous hands and calendar keep it readable and useful underwater and on land. The 44mm case diameter and 51mm lug-to-lug fit a broad range of wrists, and the 22mm strap width means the bracelet can be swapped for a strap of the same size. It comes with a 2-year warranty and a carton packing box.