Shellac is actually the brand name for a nail product and is made up of a mixture of nail polish and gel. There are over 100 shades of colours. Shellac is applied like a regular nail polish onto natural nails, so it cannot be used to extend them. However, the gel component in Shellac will add strength and durability to the nail and in the long term, Shellac won’t damage your nails as much as traditional fake nails. A Shellac manicure should last up to two weeks or more.