The Alpine MusicSafe Classic, Alpine MusicSafe Pro and Alpine MotoSafe include different sets of filters. You can change the filters for more or less attenuation. Pull out the filter from the earplug. The filter has a tight fit so make sure you pull firmly to get it out. Don’t be afraid to damage the earplug when doing so. After the filter is out, you can insert the other one. Of course, don’t forget to do the same with the second earplug.