Protecting an air filter or nearby components from radiant engine and exhaust heat. An open cone filter sitting in a hot engine bay draws hot air, which is less dense and undoes much of the benefit the filter was fitted for. A shield blocks the radiant heat while allowing airflow.

2.25 to 3.5 inch filters, which covers the great majority of aftermarket cone and foam filters including our Filtech range. Check your filter's body diameter rather than the neck size, since it is the body the shield has to clear.

T6063 aluminium - lightweight, corrosion resistant, and effective at reflecting radiant heat. It needs no coating to survive in an engine bay and will not rust. Available in silver for the raw polished look or black for a more discreet installation.

Yes, where the filter is genuinely exposed to radiant heat from the exhaust manifold, turbo or radiator. Cooler intake air is denser, which is the whole point of an induction change. On a filter already tucked into a cool corner, the gain is smaller - it depends on your engine bay.

Purely cosmetic - the material and construction are identical. Silver suits a polished-pipework show build; black disappears into a dark engine bay, which suits people who want the performance without the aftermarket look. Both reflect radiant heat equally well.

Position it between the filter and the main heat source - usually the exhaust manifold or turbo side - and mount it to a solid bracket or existing fixing point. Leave clearance around the filter so airflow is not choked, and make sure the shield cannot vibrate against the filter or bodywork.