Sorry for the lateness in my reply...just seeing this thread.
The Delta 200 works best for the Adamo Prologue. The Delta 225 was designed for Adamo saddles with a transition hook. You can technically mount the Delta 225 on the saddle, but you really don't need the U-hook that is on the top when mounting on a Prologue.
Candice Turner
CEO
XLAB - Aerodynamic Triathlon Accessories
Dawn to Dusk - Off-road Specific Storage Accessories
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