Take a look at the Spinelock review by bikepacking.com Sizing
There are two size options, neither of which sacrifice features for capacity. The smaller but largely versatile Spinelock 10L maximizes your carry with minimal tyre clearance and provides a generous amount of waterproof storage with additional space on the external corded deck. If you are going on a long expedition or carrying cold weather gear we recommend checking out the Spinelock 16L.
The 10L Spinelock requires 20 cm tyre clearance and 16.4 cm exposed seat post Features
Innovative Spinelock stability system completely eliminates side to side sway
Two mounting positions to accommodate seatpost setback and saddle adjustments
A low profile, high strength, forged aluminum clamp works in combination with precision IGUS bushings to form a quick-release pin interface making bag removal a cinch
Quick release bag from bike
Internal HDPE plastic structure
One way, low profile, air purge valve
Carbon seatpost friendly
Hypalon slots for a rear light
Top mounted external webbing and bungee for additional storage
Protective external plastic bottom frame sheet
Active cam buckles prevent side straps from slipping on rough terrain
Traditional saddle style rails are required. Does not work with most Brooks saddles. Does not work with most Brooks saddles including (B17, B66, B67, Flyer, and similar). Spinelock is compatible woth Brooks Cambium line (C15, C17, C19).
Minimum 20 cm tyre clearance and
Minimum exposed seat post 16.4 cm
Important information on use and fit
The Spinelock bag is not compatible with carbon fiber saddle rails
Only compatible with traditional style saddle rails and is not compatible with most models of Brooks saddles including (B17, B66, B67, Flyer, and similar), Spinelock is compatible woth Brooks Cambium line (C15, C17, C19).
This product is not designed for use with dropper seatposts
This bag is for carrying soft, pliable objects. sufficiently pad any hard edge objects like cookware to prevent premature wear
It is mandatory to check tyre clearance prior to use, especially with full suspension bikes. Bag contact with a tire can cause a bad wreck and ruin your day. Tyre damage to the bag is not covered by warranty
A Torx-25 wrench is needed for installation. You likely already have one on your multi-tool!