Not sure how many liters the Castelli saddle bags are, but, I use the mini on both my Exploro and Strada. The Exploro has a 2” 650b tube, Specialized Emit 9 tool, standard Allen wrench for the axle, 20g cartridge and chuck, and a boot patch. With a a 700x28c tube, I can fit all that plus a second cartridge. If you want a second tube and second cartridge, go with the XL bag.
https://www.castelli-cycling.com/us/men/accessories/cycling-bags