Depth Gauge SOS (Made in Italy) Vintage - Sold as is (for parts/repair)

This is a vintage SOS (MADE IN ITALY) depth gauge for scuba diving, sold as-is (junk).

I used it as a backup to my dive computer, hanging it from my vest. I purchased it new at the time, but it is an old item from about 25 years ago. The surface of the strap has become white due to age, but there are no cracks or tears. Please check the photos.
Also, I am selling it as junk because I am unsure if it functions perfectly as a depth gauge.
Please check the blue circles in photos 14 and 15. Photo 14 shows it in normal condition, and photo 15 shows it submerged in a sink filled with about 15cm of water.
It appears to be functioning, but I cannot confirm anything further. Please understand this before purchasing, and we ask that those knowledgeable about depth gauges purchase this item.
Unfortunately, we cannot accept complaints or returns.

Shipping will be via RakuRaku Mercari便 or YuuYuu Mercari便. The shipping method will depend on our convenience at the time. Please understand.

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As this is a personal item stored at home, there may be oversights. For this reason, please refrain from purchasing if you are concerned about details. We are not considering price reductions.
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