Thanks. I just replied on the other thread, I'm looking for the link to that whistle that replaces the sternum strap on a backpack, going to add to theirs when I get them.
Here's the one I'm familiar with:
Nexus 20mm Airlock WhistleThat's a Canadian retailer, though. You could try looking through the list of
distributers at Nexus' site for a seller state-side.
Nexus also has a
zipper pull whistle that might be worth looking at too.