Catalytic converter

Standard CAT

A catalytic converter (colloquially, "cat" or "catcon") is a device used to reduce the toxicity of emissions from an internal combustion engine.

See Catalytic converter on Wikipedia for further information.

S1

Elise S1 catalytic converter

Pre-TF MGF's have the same cat as an S1.

S2

Elise S2 catalytic converter

The S2 CAT is different from the S1.