Audi A6 C5 4B Allroad
Rear Left Air Spring 
DUNLOP 4Z7616051A (Bellows ; Air Suspension) 

Your advantage:
- 2 Years Warranty (against manufacturing defects)
- Quality product
- More cheaper than authorized repair
- Specialized technical advice
- Deliveries in 24h (unless out of stock at manufacturer)

Important:
- Make sure after repair that the system is absolutely leakproof, Any leak on the system compromises the functioning of components such as the suspension compressor.
- When you replace the air suspension compressor,you must  always change the relay before installing the new compressor even if it seems to still work.
- This is a specification by the car manufacturer.