Great bag alternative to a saddle bag to keep your bikes aero look. BUT IT IS NOT LABELED “ Roswheel” as shown. Too bad. Nice bag.

I don’t like to bring a lot of extra stuff and think that one seat bag should really be sufficient for anything up to maybe a 40 or 50-mile ride or a bit more on a regular ride.But every once in a while I need a little extra room, the Roswheel Race Series Under-Top Tube bag is perfect for when I need a bit of extra space.It’s a good fill-in bag I guess you’d say.And it does this job well and looks great doing it. Like all of the Roswheel stuff bags that I’ve gotten, it’s manufactured extremely well.It’s made up of some sort of waterproof material and has a bit of padding with a bluish waterproof coating on the inside, the company claims the material is very tear-resistant but lighter. The zippers are even YKK water-resistant zippers, kind of hard to go wrong with quality like that. The rear strap has a bit of a wider additional section and the part that goes under the strap and comes together allows you to pull the strap closed to hold it in place on that bar.There’s a mesh pocket in the back of four cards ID or money or whatever. Like most of Roswheel’s bags, the sewing seems to be really good quality.The underside has a textured rubbery material which I assume is even more weather resistant than the overall bag, and double helps prevent water from soaking in that might come up from the road from beneath I suppose.And if you are concerned about it – it is kind of aero. Weight is 99 grams or around .22 pounds and the company claims .6 liter (.26 gallon) capacity. Of course, it depends on the shape up what you are trying to fit into it. It is around 14 inches long with the zipper length being around 10+ inches and barely wider than a top tube – about 4.1 cm (1 5/8 inches), so you don’t have to worry about your legs or legs hitting it – whether sitting or standing.It’s fairly small and unobtrusive, and it goes on the bike quickly and it can be taken off just as quickly using the three straps and matching velcro. Two straps fit around the top tube and one goes around the seat post. You could stick it on top of the top tube, I think, but it’s really made to go underneath. There is enough extra strap length to fit around a mountain bike tube also. Really, less than a minute taking it off or putting it on. And the straps are cutable if you think they are sticking out too much.And really it looks nice, and the Roswheel logo and striping is reflective too.It’s not quite large enough for my phone unless I really stuff it in but I usually put my phone in my seat bag or my jersey. But for extra gels, protein bars, large car remote keys, maybe some lunch items (but not a sandwich), even an apple sliced up in Ziplock bags, a battery pack charger, extra Co2 cartridges – all those extras fit just fine when you don’t want to stuff anything in your regular seat bag or your jersey pockets. Personally, I don’t like a bunch of stuff in my jersey pockets, and things like protein bars may start to melt if you are cycling hard.If I’m going on a longer trip and I just need a couple gels or a granola, or the day is looking intermittently cloudy and I might want to take off my sunglasses and store them somewhere easily accessible and scratch/crush-free it’s good for that, or maybe I want to carry something small with me like an extra tube or an extra tool or tube. I also may want to carry something in there that I can easily carry elsewhere but the bag gives me the freedom to stick it in there instead, more easily and accessible. Maybe like some money or a credit card or gift card because I’m stopping somewhere, it’s really easy to get open and get stuff out versus sticking something in the seat bag with my tools and phone.The only negative I suppose – and this is not the fault of the bag; is that with a fairly compact frame a high water bottle it may come pretty close to the bottom of the bag. No way around this I suppose, without using a tube top bag instead or even using this on the top of the top bar instead.So, I believe that the Roswheel Race Series Under-Top Tube bag is a great little convenient extra thing that can be thrown on easily. At least for me, for others they might stick an extra tube in there or some tools and maybe even use it as their primary bag. But it is fairly small, smaller than a seat bag normally is but for those who go the very minimalist route or carry most of their stuff in their jersey, this might be a good additional bag for them also.I mean, the thing looks and feels substantial, it’s hard to go wrong with the price and quality of the bag. Even if you only use it once in a while. It really looks more expensive than it is.

This seems to be a well-made small frame bag, with quality fabric, attachment straps and zippers. It is most suitable for a road bike. The width is very narrow. It will hold a 700c x23-28 road tire, tire tools, a mini-tool and a small set of keys but not much else. A 26x1.75 hybrid or mountain bike tire is too wide for proper fit although if you don't mind a bulge it would probably fit. Pay attention to the (accurate) measurements on the webpage before ordering.

Works well for me. Needed a better way to carry tools and tubes on my road bike used for triathlons. Bento boxes only really fit nutrition, most other bags aren't aero at all. This is the best compromise I have found.

I was looking for a bag small enough to hold my wallet,keys, garage door opener. This bag is perfect for the need. Not some bulky bag like others. The bag has a nice sleek look to it.

I like that it is Slim - not Bulky - Just enough to carry Tube, a few tools and CO2 cartridgesNo room for iPhone though - I knew this getting it

The frame bag is pretty small but very aerodynamic for race day. Won't fit a phone but a multitool, air canisters, and spare tube are no problem.

Kinda small but a Good bag if you have limited space. Fits a tube, levers, and a couple more small miscellaneous items.