I love the ear protection we've got, it's active, with sockets for connecting them to the audio outlet of a com-radio there is also another version of them with an integrated boom mic, effectively making an ear defender/headset. The active part consists of two stero microphones on the front of the cups and speakers on the inside with automatic kill-switches set to 80dB so that if the microphones pick up a sound of that magnitude, the speakers inside are momentarily turned off until the sound has returned to acceptable levels. Also the volume controls make it possible to hear other, softer sounds even better than without anything.