The Wpro cooker hood carbon filter CHF28/1 C00380120 offers an absorbent action that protects against the spread of bacteria in the air, giving you a healthier environment, and reducing the risks of allergies. The performance is increased with the AC 40 quality charcoal. Its ability to absorb odours is 2 x greater than that of a traditional charcoal (AC 20). The auto-extinguish feature guarantees totally safe use (conforms to standard UL94: V-2). To ensure optimun performance it is recommended changing it every 3 months or when the indicator chage its colour.