Hardware: Specialites T.A. Set #25 Chainring Fixing Bolts
This set attaches the large outer chainrings (and all subsequent chainrings) to the Pro Vis 5 "cyclotourist" cranks. You need these.
These also work with Velo-Orange, Sugino PX, Shimano Deore/Maxy, and the cheap Sun XD cranks.
Made in France.