Unlike a lot of other timers, it actually has a vibrate feature that means you don't have to experience loud beeping to know when your time is up (great if you train with headphones on). (fitstep.com)
The witness looked down at his geiger counter and sure enough, it was making that really loud beep that means something bad will happen. (lawyerist.com)
One second later, they both heard a loud beep. (procrypto.net)