PrimoChill Intensifier Transparent Dye Pack (11 bottles) Used to alter,change or intensify existing coolant colors! Formulated to provide the most Intense and vivid colors possible with "intense" quality inspection. Stongest, Most Powerful Industrial Dyes but still clean and pure with no special additives. Environmentally responsible safe and non toxic product. Safe on all plastics, rubbers,and miscellaneous gasket materials. Each Bottle is labeled with a batch date to insure freshness. 2 year shelf life (unopened in original Black Out Bottle)