Predator Turnabout

"Sloane had ear-protectors-you had to wear something when shooting big bore weapons, else you'd go deaf. His were electronic, in that they compressed noise over a certain decibel level, dropping
it to a safe level, but allowed normal sounds in. More, they could be turned up, to become amplifiers that would allow you to hear things you normally couldn't. Sometimes called "wolf ears," the
hearing protectors were ear muffs, like old-style radio operator headphones, and when dialed up, you could hear your own
breathing."

"Useful that, when you were in the woods."pg.88 chpt.9