Test The Extremes With The Citizen Promaster Tough Series, Now Featuring Chronograph And 12/24-Hour Time. Living Up To Its Name, This Timepiece Features Shock Resistance And Anti-Magnetism. A Black Ion-Plated Stainless Steel Case With Citizen's Proprietary Duratect Surface Hardening Coating, Allowing For Anti-Rust, Scratch Resistance, Hypo-Allergenic And 5X Harder Than Stainless Steel. Other Features Include Camo Patterned Ballistic Nylon And Polyurethane Strap, Black Dial, Anti-Reflective Sapphire Crystal, Super Luminova Hands And Markers And Ability To Function In Extreme Temperatures. Featuring Our Eco-Drive Technology – Powered By Light, Any Light. Never Needs A Battery. Caliber Number B612.