Porsche Cayman Boxster 987.1 Stainless Manifolds & Cats to fit Gen 1 by Topgear. This is a pair of high quality manifolds with built in cats (manicats), a combination both conserving weight as well as torque and boosting the sound and performance of the 987 like any high quality aftermarket exhaust product should. These manifolds have been designed from scratch for the Porsche 987 and fit perfectly to the car's OE system or to any of our other aftermarket products that fit this vehicle. This product listing includes all required gaskets for both manifolds, so you can buy in confidence. The cats in this item are both 200CPSI catalytic converters..