FMG is short for Forton Modified Gypsum or Forton MG. It is a unique combination of high-strength alpha hemi-hydrate gypsum with water based polymer chemistry that is reinforced with "E" glass fiber. FMG is the first technology to make gypsum an exterior product, when painted or sealed. It's a versatile, lightweight material that easily lends itself to many production techniques and can easily achieve a range of attractive architectural looks.