Novoflex PRO-EOS Adapter Ring - to Connect Lens-End of EOS-Retro to BALPRO-1 or T/S Bellows 
The Novoflex PRO-EOS Adapter Ring allows for the benefits of the EOS-Retro to be applied to the Balpro or T/S bellow systems.
This adapter fits in between the EOS-Retro and the bellows, at the lens end. When using a Canon EOS camera with an EOS compatible lens, this combination will transmit all lens-to-camera information.