Review on Topeak Wedge Pack II Seat Bag with Micro F25 Fixer Black: Compact and Versatile Storage Solution for Your Cycling Essentials by Jeff Dabney

It's very small, but I can fit a 700c 35/43 pipe, a small bike tool kit, some nitrile gloves/hand sanitizer, a spoke wrench, and there's still room for a few coins, plastic hair covers (seat cover, bag if wet weather) and possibly a key. I like that it only has one attachment point on the seat. You need to have about 1cm clearance from the horizontal rail of the seat to attach the bracket. The reflective tape is very effective.