This is a replacement derailleur hanger and two of the tiny bolts for any of the following Crust Frames:
Bombora, ENVE Bombora, Evasion Lite, Nor'Easter, Disc Lightning Bolt, and Disc Romanceur.
It's wise to keep an extra one of these floating around, especially if you're touring.
Weight (Oh yeah, we weighed one)- 14g