Too absorbed by brand names are we? TV does that.. its the Advertising..


going to dimensions ..
Bicycle chains standardized on 1/2" pitch and so any chainring of the same tooth count will be the same diameter.

the other data point is chainring bolt circle diameter..

a 74 bcd 5 bolt chainring is interchangable with any other of same data.

dont think there are 42t 74mm bcd chainrings


FD just shove the chain sideways off the chainring to another .. de rail ing.