Rockwool Slabs and LRB (Lightly Resin Bonded) Mattresses are high-density, fire-resistant, and non-combustible insulation products manufactured from volcanic rock, typically used for thermal, acoustic, and fire insulation. LRB mattresses are flexible, often wire-meshed, and ideal for high-temperature applications like pipes, boilers, and industrial tanks up to 750°C, whereas rigid slabs are suited for building structures.