Rockwool Comfortbatt insulation for wood studs and joists. It is a stone wool insulation product for use in both new residential construction and renovations. This semi-rigid batt has a unique flexible edge designed to compress as the batt is inserted into walls, attics, ceilings, and floor frames. The flexible edge springs back, expanding the batt against the frame studs to give a complete fill. Rockwool Comfortbatt compensates for normal variations in stud centers caused by distortion or warping. The special flexible characteristic at the insulation edge ensures the expected R-value is achieved. Key properties: Easily cut; non-combustible; excellent sound absorbency; does not rot or promote growth of fungi or mildew; low moisture absorption; and water resistant. CFC (chlorofluorocarbon) and HCFC (hydrochlorofluorocarbon) free product and process. Made from natural and recycled materials. Rockwool can contribute to earning LEED (Leadership in Energy and Environmental Design) points. No. RXCB351525: Insulation R-Value: R-15, Size: 15-1/4 In. x 47 In., Thickness: 3-1/2 In., Material: Stone Wool Insulation, Coverage: 59.7 sq ft/package, Pkg Qty: 12, Package Type: Bag No. RXCB551525: Insulation R-Value: R-23, Size: 15-1/4 In. x 47 In., Thickness: 5-1/2 In., Material: Stone Wool Insulation, Coverage: 39.8 sq ft/package, Pkg Qty: 8, Package Type: Bag No. RXCB5523: Insulation R-Value: R-23, Size: 23 In. x 47 In., Thickness: 5-1/2 In., Material: Stone Wool Insulation, Coverage: 39.8 sq ft/package, Pkg Qty: 5, Package Type: Bag No. RXCB3023: Insulation R-Value: R-30, Size: 23 In. x 47 In., Thickness: 7-1/4 In., Material: Stone Wool Insulation, Coverage: 29.9 sq ft/package, Pkg Qty: 4, Package Type: Bag No. RXCB3523: Insulation R-Value: R-15, Size: 23 In. x 47 In.., Thickness: 3-1/2 In., Material: Stone Wool Insulation, Coverage: 59.7 sq ft/package, Pkg Qty: 8, Package Type: Bag No. RXCB301525: Insulation R-Value: R-30, Size: 15-1/4 In. x 47 In., Thickness: 7-1/4 In., Material: Stone Wool Insulation, Coverage: 29.9 sq ft/package, Pkg Qty: 6, Package Type: Bag