Epistatic White, Epi, Dominant White or Epiwhite as commonly called, cause the coat to be entirely white. Not a single speckle of color will be seen throughout the entire coat.
This is NOT to be confused with albinism, which often causes redder pigmentation around the points, red pupils and very pale blue, pink, or lilac eyes. More can be found about Albinism in the points section.
White should always be white or off-white.
SAT 0-10
VAL 90-100
It can get a bit repetitive when you get a couple of epiwhites. However, there's some alternatives for differentiating them and add a little bit of spice to them.
Overcoats
As long as both shades of colors are within acceptable white ranges, Epiwhite cats may show an overcoat.
Please keep in mind that overcoats may not be used to create shapes