Hi Brooke, Thank you for your enquiry. According to the Car Seat adapter guide available online under this product, the Baby Jogger City Select Car Seat Adapter is not compatable with the Britax BOB Car Seat. For further information on this or any of our other products available, if you follow the link https://www.babyonthemove.co.nz/store-locations/ this will take you to our online store finder. Here you can find contact details for your nearest Baby On The Move Store where one of our team experts will be happy to assist you in your product search and help answer any further questions you may have. We hope this has helped with your query.