Originally Posted By: bentirran

Whistle - Try an Aluminium Lifeventure model -smaller form factor and fits better into the PSK rather than the plastic ones.


I would suggest a better whistle than the novelty key chain variety ; also a metal whistle is not ideal under all condiditons.
Metal whistles can stick to your lips in freezing temps.

Stick with a plastic whistle that is designed for emergency / survival signaling. These types have been tested and approved by SOLAS and the US Coast Guard for this type of use; Storm, Acme and Fox 40 are good ones.