Vintage double hose dive in Crystal Falls, MI at a nice & clear (but cold) quarry known as Fortune Pond. I know the video is shaky and dark but so was the dive. Max depth was 83' and the temp below the thermocline was a balmy 44 degrees. If you pause just right at about a minute 12 you can see this.
The regulator is a vintage US Divers Aqualung single stage Mistral from the late 50s with new hoses, o-ring and diaphragm. Its such a simple design and it breathes so well its no wonder it was a favorite of Jacque Cousteau.
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Please watch: "Finding Jewelry, a pipe, fidget spinner and laptop in popular swimming area"
https://www.youtube.com/watch?v=vzjmYU6c3Gc
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