The medium size (with zipper expansion if needed) fits nicely within my 145mm saddle dimensions, is secure and well-made. Swallows a bagged 25mm tube, tire tools, multi-tool, wallet and clamshell cellphone, couple tubes of Neosporin, couple individually wrapped sterile wipes, eye drops, cut-tire patch. I've used the zipper'd expansion only once, but it came in handy. (Riding home holding an acquired item in one hand is such a drag.) Would buy again. (Would have preferred dual zippers on the back, but all the other features still add up to best I've used.)
The medium version is perfect if (like me) you want to carry 2x-tubes, 3x CO2, inflator, tire levers and a mini-tool. Mounting is easy and stable (go w the strap & buckle option). Bag size will not bump your legs if properly mounted.
Bought both a medium and a large. One for my wife's bike and one for mine figuring a could steal hers if I needed something smaller. Been doing some longer gravel and xc rides where the additional volume has been a nive feature without being overly bulky. Snugs down nicley with no floppping about.
It's a wedge pack, so not much to say other than it functions exactly as I hoped. Attaches very securely without fuss, no movement or rattling. Small, but holds two tubes, two C02 cartridges, a C02 inflator, patch kit, multi-tool and one misc. item (energy bar, keys etc.). Simple and clean design. I'm so far very happy.
After years of fussing around with various size and attachment methods, I've settled on this pack as the most versatile option for single day rides on road or cross bikes. Size small is the right size. Medium is too big unless you want to fit 2 29'er tubes - otherwise a small will fit 2 cx tubes with room to spare.
Don't bother with Velcro or custom attachment methods (fizik).. go with straps and clips like the topeak.
Downsides not at all waterproof. Pack can bump legs depending on position.
The medium is tight for anything more than a tube and a few tools. It's virtually impossible to squeeze in a wallet and cellphone. But my biggest frustration is the placement of the zipper. With the bag snugged up tight under the seat (which I assume is how it's supposed to work) you have to squeeze your fingers between the bottom of the seat and the bag to open or close it.
This saddle bag is very nice and has a lot of room to put a few inner tubes, multi tool, and your CO2 inflator and cartridges. It has an expandable zipper around the middle if you need to add more stuff. I would have given the bag a 5 star rating, but I don't like the long straps that dangle on both sides. Perhaps they could have put a bit of Velcro on both straps so they won't dangle and flap in the wind.
I was looking for a large bag to replace an old performance wedge. This fits pretty much everything for me. Tube, 2Co2's, levers, keys, cell, patch kit, gloves, small wallet, eye glasses, and pretty good size first aid kit. I like the straps under the bag because it holds my pump (mini-morp).
It's big and ugly on the back of your road saddle, but it holds a lot of tubes, tools, and other stuff, so you'll probably never get stranded. After they're done mocking it, my friends all wish they had one. The loop strap on the back is also a convenient place to put your rear taillight when you're riding in the dark. I've got a couple of these bags now- they really work great.
I bought this product to be able to carry a spare tube, my tire irons, and a few bike tools. This bag easily accomodates all of these items with a tad to spare. I like the styling and rugged construction, and use the light strap on the back for one of my rear flashers. This is a good product.