Dow ‘s Active Protection System is a “smart” textile that remains soft and flexible until it is struck by high-impact. The active ingredient in the fabric is a dilatant silicone coating, which is a shear thickening fluid (STF). The viscosity of this coating increases with the rate of shear, therefore defining it as a smart material as it responds to changes within its environment. By high-impact force, the material instantly stiffens. When the collision has passed, the material immediately becomes flexible again.

The Active Protection System is breathable and flexible for good comfort and freedom of movement, and it can be stitched directly into garments, eliminating the need to insert and remove components. It is less bulky than hard armor, allowing for many design possibilities. The washable fabric can be layered to provide customized levels of protection for specific areas. It also integrates easily into existing manufacturing processes.