NiteCore NWS10 is the loudest emergency whistle on the market. You can effortlessly produce 120 decibel sound. Made of titanium alloy, NWS10 is durable, lightweight and compact. This is 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. This whistle also utilizes a precision Teflon resonator and has a high or low temperature-resistance.