• Fits Niner Eccentric Bottom Bracket (EBB) bikes with a ~55mm ID. 
• Found on all Niner EBB bikes and some other brands
• TO convert your EBB bike to a BBSHD mid drive

Limitations

This adapter provides a standard BSA 68mm threaded shell  compatible with 68-73mm BBSHD/02 axles. 

Looking for standard American style eccentric adapter?

This size is a bit smaller inner diameter. See this link.