C-Bear took a very early position not to use plastic cups (back in 2011/12 when most were adding all sorts of plastic accessory parts to force the 2 components – bicycle bottom bracket shell and crank – to fit).
Metal alloy housings requires:
No tendency to deform
Designed to place C-Bear ceramic bearings next to the crankarm for optimal stiffness and maximum power transfer.
Eliminate unecessary add-ons
Eliminate lose parts (spacer, wave ring, adapters….)
No loctite (glueing)
optimal tight fit, just press-in.