This sample bag of the F3 Industrial Felt gives you a 3 inch x 3inch square each of 1/2 inch, 1/4inch, and 1/8inch thickness. SAE F-3 Felt is minimum 85% gray wool and has a density of 0.32-0.36 g/cm3. This high-grade of felt is suitable for vibration absorption, resistance to abrasion and wear. F3 felts offer the same uses as F1 felts but are of slightly less density and durability. The sample bag is a perfect way to match and select your grade of felt and be able to physically feel the felt. These can be kept in your swatch library to refer back to or for applications that need a smaller amount of industrial felt to work with.