RAWstinwrote a review of Timbuk2 Bicycle Seat Pack on October 30, 2014
Familiarity: I've put it through the wringer
I got the medium to put on my mtb bike and 1 tube barely fits and not much else. probably rad for a roadie but a bit small for my needs. The 3 velcro straps are good and are really secure, but the zipper isnt very accessible under the seat unless you loosen the velcro.