Acoustical Fire Batt (AFB) is a lightweight, semi-rigid batt insulation specifically designed for steel stud interior wall and floor applications. AFB Evo is a no added formaldehyde insulation. This stone wool-based insulation is made from natural stone and recycled content. Its a sustainable product that provides superior sound absorbency and fire protection for overall occupant comfort and safety. Thats why AFB is quickly becoming the insulation of choice for todays green builders in commercial and industrial construction.The AFBproduct comes in a number of thicknesses to meet the requirements of both retrofit and new construction applications.