Arnott Air Springs A-2133. Heavy Duty Multi-Ply Rubber Air Bladders: Arnott Air Springs are made with durable, multi-ply rubber bladders, reinforced with fabric, ensuring long life of the air springs.
As close to OEM quality you can find at a fraction of the price.
The only brand I trust other than Audi for air springs. I have installed several pair and never had a problem. A couple pairs I have on c5 Allroads for over 5 years now. Definetly would purchase again.