Overview Steeldive 1975 is an homage to “perfect professional divers' watch” in 1975. One of its innovative features is the ceramic protective shroud that makes the watch extremely robust and also very distinctive. Aficionados thought it looked like the wearer had a can of tuna strapped to his wrist, hence the nickname, “Tuna”. Watch Specification Model: SD1975Movement: Japan NH35 automatic, 41 hours of energy storage. Case material: 316L stainless steelCase back: 316L stainless steelDial: Black, sunburst blue, sunburst greenBezel: 120 clicks unidirect rotational ceramic bezelWatch mirror: sapphire crystal with AR coating.Water resistance: 300m / 30 ATMLuminous: Swiss C3 green and BGW9 blue super luminous.Crown: Screwdown CrownCase back: Screwback Case Watch Dimension Case diameter: 47.5mm ( without crown)Case length: 44mm (lug to lug)Case thickness: 15mm Lug width: 22mm  Our service Warranty: 2 years Delivery: DHL Returns policy: 30-day return and refund.Style: automatic watch, dive watch, luxury watch Package: watch, box, warranty card, user manual