Let's get packing, bike packing that is! From Revelate Designs:
The Pika™ is a smaller version of the Viscacha with side panels that are 1.5" shorter in height. The Pika's shorter height makes it ideal for minimalist bikepackers, big day rides, women riding smaller bikes, full suspension bikes and others without much tire clearance or exposed seat post.
Many winter bikers are also using this bag for day trips as a place to store a puff jacket or other warm layers.
Requires a minimum of 3" of exposed seat post and 8" of clearance from saddle rails to tire. Check tire clearance with bag loaded and properly packed prior to use to prevent bag damage or worse. On full suspension bikes, fully compress rear suspension and check tire clearance prior to use.