Here's what Omnium has to say:

A pair of new CXC mudguards.
Matt finish.
Rubber mudflaps front & rear.
All fittings included.
50mm outer width.

The CXC frameset has 55mm clearance between the chainstays, so a 700x43c tyre is the biggest we can recommend in combination with these 50mm mudguards!

Without mudguards it is possible to fit a 700x50c tyre in the frame, but be warned that the clearances will be tight.