Owens Corning 705 Rigid Fiberglass Boards (RFB) is called for in some bass trap and sound absorber designs.
Specs and Features:
If you need 4 or more pieces, order Owens Corning 705 2 inch Case of 4 here.
For a formaldehyde free alternative, consider Knauf Acoustical Insulation 2" 6lb Boards.
To see more detailed information, check out Selecting the Right Acoustic Material for a comparison of all of our insulation materials.