https://www.wristwatchreview.com/3-technologies-to-know-sinn-ux-ezm-2-b-hydro/

Sinn is now owned by Lothar Schmidt who was the production director for a few little companies called, IWC and A. Lange & Sohne.  In the early 90s, they focused on technology as a way to distinguish themselves from other watch companies. I think three uses of technology stand out with the Sinn UX EZM 2 B Hydro.

I could read the time at the almost any angle. The technology requires a quartz movement which is a downer for me, but the battery is no ordinary quartz battery and only needs replaced every seven years. When I say replaced, I mean send it back to Germany to have them change the battery. Don’t take it your “watch batteries while you wait” store.  Why are you sending it back?  Simple – the case is oil-filled.  While the oil inside the case enhances its dial’s visibility; it also enables the watch to dive deeper. This sucker is rated at 5,000 meters, or by my math, 100 laps-deep at my neighborhood pool. (Kids, Daddy’s going to need the floaty.)

Secondly, Sinn uses a few tricks with its cases to enable your dive watch to stand up to your reef or my pool recliner. Can you say: German submarine steel. Yep, sub steel from a shipbuilder in Emden Germany on the North Sea. The benefit here is its resistance to sea water, of course, but they don’t stop there. This steel has no magnetic properties (it cannot be magnetized), so it protects the watch against 4,800 A/m magnetic fields. Sounds like a lot, but this is about as strong as a refrigerator magnet, so keep it out of your neighborhood MRI machine which emits several million A/m.

Lastly, Sinn also use a technology called, Tegiment (“tegimentum” in Latin). This process hardens stainless steel cases to incredible levels. They want you to understand it’s not a coating but instead a process that hardens the surface.

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