"It's a battery, it works...there's not much else to say."
I have a Suunto Observer I was suuuuper sad when I realized my Suunto had died :(. But I just ordered this and replaced it and now its all guud! Important to note: this is just the battery, it does not come with another backing as the picture might lead you to think. So if you need a new seal or backing that is separate. It is also not a "Sony" it is a Energizer battery. But it still works so I am happy.