It's high density, for bass traps.
High density? For BASS TRAPS??? Are you SURE about that?

How is that going to work? 100 kg/m3 is waaaay too dense for bass trapping, if you ask me.
Contrary to popular belief, higher density is WORSE for bass trapping than low density, not better. Bass trapping is usually accomplished with lower density, while high frequency absorption benefits from higher density, but 100 kg/m3 is overboard.
Like Glenn and John said: 15 or 30 kg/m3 is much more like it for bass traps. Maybe even 45 kg/m3, depending on the type of insulation. But if you go much higher than that, then you start losing effectiveness for low frequencies
- Stuart -