It sounds like you might need the # TH33RV which is an M6 bolt that is 35mm long and will allow you to mount Thule bike trays to the Aeroblade crossbars. view full answer...
If you are talking about the Grease Cap Plug for E-Z Lube Grease Caps, the part that you are looking for is # RG04-010 which comes in a quantity of 2. view full answer...