A sachet is a small sealed bag or packet containing a small amount of product. Sachets usually comprise of material made up of more than one layer to ensure that there is a barrier of protection between the contents of the sachet and either oxygen or light. An example of this material would be a 12/9/60 triplex lamination, in which case the material would consist of 12 microns Polyethylene Terephthalate (PET), 9 microns Aluminium and 60 microns Polyethylene; where Aluminium is the barrier against light, oxygen and moisture. Many other options on the material are also available.