Marine 861 UltraFair is a convenient trowelable filler developed for fairing large surface imperfections on aluminum, steel, fiberglass or wooden marine vessels. With the cold weather hardener it is easier to mix-apply-cure during colder weather conditions. The white resin and brown hardener, when mixed together at the convenient 1:1 volumetric mix ratio, yield a smooth, creamy paste which can be easily applied up to 1" thick without sagging or shrinking during the curing process. 861 UltraFair Resin and Hardener are 100% solids systems and may be used above or below the waterline. When cured, this system features excellent sanding and finishing characteristics and accepts virtually all types of primers and paints. Note: This product is intended to be used as supplied. Do not thicken or thin this product as altering the formulation may lower physical properties. Available with two hardener options and simple 1R: 1H parts by volume mix ratio: 861 UltraFair Hardener, and 861 Cold Weather Hardener.