It seems to be that a good Visible Light strobe is probably the best (first-)choice for a light-based device ...
I had already picked up a
TekTite Mark LED Strobe to always ride in my pocket with my SMB & spool (while in big-water anyway)
- reasonably compact (5.75"), 300m rated, 1mi+ visibility, AA battery (11+ hrs w/ Akaline & 20+ hrs w/ 1.5V Energizer Lithiums)
- includes a velcro strap, but I put on a plastic clip w/ a split-ring (left over from some dive accessory) so I can clip it to the top of my SMB
TekTite Strobe-Lite
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I figured that that was good-enough to get found by my boat if separated on a night-dive, but given recent events, I'm considering getting something with more burn time ...
TekTite also makes a 3-AA version that is about twice as long (9.75"), but rated for 300+ hours
- BONUS it is half the price @ $23. I really can't understand why (and the relative price factor is about the same from Tek-Tite.com directly) although I wonder if there is something about the LED/difuser panel insert that is somehow "less"
Tektite Mark III LED Strobe
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Size comparison:
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