Thanks. I'll check into that.

This is definitely a "stealer" . . .

I think one of my packs definitely does. However, any military surplus pack I own won't.

Thanks for the link

The effectiveness of such a small whistle is the question.

Sounds like it is time for a field test. Since, I do not have one, I will have to wait.

Blow your whistle now and everyone that hears you post your location here so we can see how far the sound travels.

I am preparing to test a number of whistles to measure their decibel level and ease of blowing it. My purpose is to select the best emergency whistle for scouts. I will procure one of these from REI and include it. I have a decibel measuring device. Any advice and ideas on the best way to structure this test would be helpful.

Found them on amazon. I assume they will be of similar, if not identical, construction.

Montanero....for a SAR event, older individuals will have different hearing frequencies than kids, so would include a variety of age group

might include a directional vs. omni comparison, N-S-E-W

uphill vs. downhill

wooded area vs. open (I suspect frequency will have an impact)

orientation of the air exhaust port... most whistles are blown with the exhaust port vertical, might try lowering head to get the exhaust horizontal

I know most northerners don't recommend a traditional brass whistle with pea trill,... but I've broken several plastic ones...

I have some hearing loss in the 4000Hz range, but I perceive a brass referee style whistle to be "louder" than my 3 chamber TOPS and the mini Fox in an AMK kit...

appreciate your test...

These guys tested whistles in the field, including the Nexus buckle whistle I posted.

part 1

part 2

They measured it at an average 105.8 dB and noted that lip placement is important because it's so small, you could envelop a lot of it in your mouth if you're not paying attention.

This guy tested some whistles too, including the Nexus buckle whistle. His number for it was 93.9 dB.

Brian Green's whistle test

These two testers got very different results so I expect one's testing protocol is quite important. It goes beyond just having a sound meter on hand.