Marathon 46mm Arctic Edition Jumbo Day Date Automatic (JDD) Watch The 46mm Arctic JDD is a rugged dive watch designed for professional Search & Rescue use, specifically in bright and hazardous environments. Featuring an Arctic White dial for increased legibility in daylight operations and submersible up to 30ATM, the 46mm Arctic JDD is hand-crafted to provide ultimate endurance above or below sea-level. The outer shell of the Jumbo Day/Date (JDD) consists of a 316L stainless steel case with a brushed finish (measuring 46mm in diameter and 18mm thick), a screw-in crown, and a sapphire crystal. The unidirectional bezel with 60-minute scale and two scale quantities (1-12 and 13-24) ensures precise timing for professional or recreational diving. The JDD also features tritium gas tubes on all hour markers and the full hand set for constant illumination in low light conditions, with a double tritium marker at the 12 o'clock position and a MaraGlo™ bezel pip for easy orientation. The watch is rated for a submersibility of 30ATM, allowing the JDD to function at depths of up to 300M (1000FT) underwater.  Movement:   Sellita SW220 with Incabloc™ Shock Absorber No of Jewels:   26 Scale Quantity:   2 Scale Range:   1-12 (13-24) Calendar Type:   Bilingual Day & Date Luminous Features:   Tritium Gas Tubes and MaraGlo™ Crystal Material:   Sapphire Crown Type:   Screw-in Case Material:   316L Stainless Steel Case Finish:   Brushed Bezel Type:   Uni-Directional Bezel Scale:   60 Minute Submersibility:   30 ATM Case Diameter:   46mm Case Thickness:   18mm Lug Width:   22mm