Do I have an Old School Dopper or a New School Dopper?
We currently have two versions of the Dopper Original which are not interchangeable.
Look at the picture below and you will see the Old School Dopper with a higher thread than the New School version. Secondly, the cup on the Old School Dopper has a white ring and the New school version has a blue ring inside. The caps are universal.
Not sure which version you have, please contact us via email@example.com.