Features:

Extremely Loud: Just one puff of air on this whistle creates a piercing 100 decibel sound that'll help alert rescue teams even a mile away.
Easy To Use: Simply blow firmly on the emergency whistle's mouthpiece to alert rescue teams.
Works Every Time: This pealess whistle will work in every weather condition and won't ever get gummed up from too much moisture. 
Incredibly Lightweight: Only 0.2 oz - so whether it’s in your pocket or in your survival kit, it’ll never weigh you down.
Tough As Nails: Made out of durable, high-impact ABS plastic, which makes it powerful, rugged, and reliable. Its non-corroding design ensures the whistle will work well every single time.
One of the Lightest, Loudest Emergency Whistles Around

Specs:

Weight: 0.2 ounces
Sound Power: 100 decibel
Design: Pealess