Genuine Gas Tank Cap with Strap 8K0201550N fits AUDI A4 A5 S4 S5 Q6 RS5 Allroad – OEM part fits direct and easy… Price: $19.33 (as of 27/03/2023 01:57 PST- Details)

Make sure this fits by entering your model number.
Genuine Part: Fuel tank cap keeps your fuel tank sealed and make you get the most out of your fuel
Easy Replacement: Remove tether of the old Gas cap using some force with a tool then push new one in hole