Vintage Princeton Tectonics bottom timer with rubber mount as shown. The wrist strap is long gone but easily replaced. It appears to have never leaked, but I can't say whether it works. I tried winding it, but it doesn't run and nothing happens when I push the button on back. I am selling it as a piece of diving history for display. Perhaps you can get it running again. Check out my other items for other vintage scuba equipment.
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