The FIREFLYBatt™ is a high-density (180kg/m³) mineral fibre batt, factory-coated on both faces with a durable white fire-resistant mastic. Measuring 1200mm x 600mm x 50mm, each batt weighs approximately 6.5kg. Designed for passive fire protection, FIREFLYBatt™ is utilized to seal large openings in floors and walls, with or without service penetrations. It also serves as a linear gap seal, accommodating up to 1200mm in height with infinite length in walls, and up to 600mm in width with infinite length in floors. This versatile solution is compatible with various substrates, including fire-resistant plasterboard, Hebel Powerpanel, Pronto Panel, Speedpanel, block, and masonry for walls, as well as concrete, masonry, and fire-resistant plasterboard for floor/ceiling assemblies. Tested in accordance with AS1530.4 (2014) and assessed per AS4072.1 (2005), FIREFLYBatt™ achieves a Fire Resistance Level (FRL) of up to -/240/240, depending on the specific system configuration. Its applications encompass fire-stopping large openings and providing solutions for multiple service penetrations across diverse construction elements.