This rocker arm is designed for the intake and exhaust sides of your vehicle's engine. It is compatible with various OPEL and VAUXHALL models, including Meriva A, Astra G, Corsa B, Omega B, Vectra B, and many more. The part is suitable for engines with specific OE numbers such as 06 40 581 and part numbers 640581 and 90398840. It is engineered for engines up to number 19649024. The fitting position is for the intake side and exhaust side.