What is Fibro-Seal Technology SLIME utilises a state-of-the-art blend of environmentally friendly fibres, binders, polymers and proprietary congealing agents which intertwine and clot within the puncture. This Fibro-Seal lattice, together with the viscous transportation system (the green goo) seeks out and tightly packs itself into the puncture, preventing and repairing flats with a flexible long lasting plug. 32oz. Material: Synthetic.