Hilti’s intumescent firestop sealant FS-One Max is an improved version of the FS-One. It provides for better handling and longer shelf life. With a W-rated, multipurpose formulation, it can be used for more common through penetrations in concrete, masonry and drywall. It is easy to dispense and available in multiple package types (tubes, foil packs and buckets) to meet a variety of project needs. Its ethylene glycol-free and low-VOC content makes it an environmentally safe formulation and is non-harmful when used as directed.