Nitecore Single Pipe Whistle. Outdoor Emergency Whistle. Single Chamber.

This is not your ordinary safety whistle. Made from a solid block of titanium alloy, so there's no moving parts, and nothing to lose or replace.
The small, streamlined air pipe is easy to blow and will produce a much louder sound with less effort. This means you can blow this whistle for longer periods without exhaustion.

The titanium alloy lets you use this in cold, wet or icy conditions. The whistle body is durable against heat, cold and crushing force and will last you a lifetime.
Absolutely essential in case of emergency, aid in survival, disaster preparedness, crime prevention, campus safety, and anything else you can think of.
Lanyard hole. Utilizes a precision Teflon resonator. Lightweight, sturdy, and durable.
Perfect for outdoor events, sporting events, security and law enforcement. Works in wet or dry conditions. Boxed with hanging tab.
Don't leave home without one.

    Constructed from TC4 titanium alloy for durability
    Corrosion resistant, sturdy and durable
    "Uni-Body" construction is portable and extremely light weight
    Single chambered design emits a high pitched frequency
    Maximum sound intensity of 120 decibels at 3-4 kHz
    Utilizes a precision Teflon resonator, high or low temperature-resistant
    Simple and highly functional design
    Works in wet or dry condition
    Dimensions: 52x7x7mm
    Weighs only 4.7 grams (approximately .16 ounce).