I didn't want a bag that was huge and noticeable and this one fits the bill. The strap is a little long and there's nowhere to tuck it so it kind of hangs a little too close to the tire and brake for my comfort. Probably have to cut it off. The bag is a little smaller than I was expecting but I should be able to fit everything I need in there. Looks to be well made and hopefully durable.

I purchased the medium sized bag first.. and it was slightly to small. Ended up throwing that on the gfs bike, and grabbing large and it is PERFECT. I can fit small tool kit, patch kit, first aid kit, iphone 7 plus, and my wallet.. without expanding. secures under seat great. Quality is great for price as well. STOKED!

I love this little saddle. It sits on the backside of the bike under my seat above my back tire. I ordered a large and it's large enough to hold my small pump, spare tubes, a tube repair kit, and a few other little things like my sunglasses and bike gloves. I also love that it drops down into a larger size. I can imagine a large would only work if your bike seat was raised a pretty good distance. It also doubles to protect my backside of water and mud flying up. I love the little strap that can have a rear bike light attached to it. It is well designed and well thought out.

Inexpensive saddle bag is not that big, even in size large. I switched to the large AmazonBasics bag which is the same price but 50% larger so I can carry a jacket, snacks, and lock in addition to emergency supplies.
AmazonBasics Strap-On Wedge Saddle Bag for Cycling

I purchased the BV Bicycle Strap-On Saddle/Seat Bag (Large), as I needed to be able to hold my wallet, phone, tire pullers, a patch kit, a spare tube, and a multi-tool -- I have mounts for other items, such as a mini bike pump. After looking at the dimensions in the product details and reading some of the better reviews that offer examples of what people stored in this bag, I'm glad I purchased the large. It's not an imposing size; and, anything smaller would not have worked for what I wanted to carry.

Pros: Starting on the outside of the bag, this is a solidly-built gray-on-black canvas bag with a cardboard insert sewn into the fabric to help the bag keep its shape. The 3M reflectors, which are nicely stitched on the bag, wrap around the entire exposed portion of the shell. Adjustable latching straps are made of a sturdy nylon material, well-stitched, and will have no problem securing this bag to your bike. The rear of the bag also has a solidly-stitched strap on which to secure a bike reflector/light, given you will have to remove your seat post reflector/light in order to attach this bag to your seat post. The angle at which the bag attaches allows the reflector to show unobscured and at a good angle. The bottom of the bag has a solidly-sewn guide through which to thread the strap that secures the strap to your bike seat. The curved, rear portion of the seat has a quality-built elastic band with solid velcro (both of which are stitched well) to attach the bag to your seat post. Buckles are made of a durable plastic and are also stitched securely. Zippers are nicely constructed with pulls on them to assist with use -- from the bottom expandable-compartment zipper, to the zipper that opens the bag's mouth, they simply feel durable. Inside the bag, on the mouth of the bag, you will find a key holder and a mesh compartment to keep cash, cards, change, etc. Both are solidly stitched. The bag itself has a nice inner lining that seems like it will survive tougher rides and jarring. Looking at the dimensions posted on the product page for the large bag (7.5" x 3-4.75" x 2.5-4"), I needed the large to carry the contents I wanted. I posted a pic showing my wallet, phone, and car keys in the bag (unexpanded), it could definitely hold a little more unexpanded and even more when expanded. I have yet to purchase a tube, but I'm sure it will accomodate all I want.

Cons: Being nit-picky, while the zippers work well, the one that opens the mouth can be hard to open given you have to slide it over the mouth of the bag (basically against the bottom of your seat) to open the mouth. Still, I'm not sure how you could improve this design, as opening the zipper from the bottom could result in your contents spilling out.

General Comments: I use the term "quality" a lot in this review"¦ that's because that's what this bag radiates"¦ quality. It's large, but not so large that you will hit your thighs when pedaling (I provided a pic of its width under my stock Giant MTB bike seat to show you what I mean). While other reviewers noted the medium and smaller bags worked well for them, for me it was large or nothing -- without going the top-tube-bag or rear-wheel-saddle-bag route. The other sizes, when hung on my bike (and I measured and remeasured to envision fit), would be too small for my needs. Neither a pro or a con, as the product description doesn't call the bag out as being such, while the tight nylon weave would indicate water resistance, I do not foresee this bag being water proof. As such, we'll see if some sort of sealant might be needed on wetter rides.

Recommended Purchase: Do I recommend the purchase of the BV large black saddle bag? The simple answer is... absolutely. This is a solid four-star product (for my needs). Fit, style, and finish on this bag all equate to quality. For toting smaller items, you simply can't go wrong with this purchase. Now, if you need to carry the kitchen sink, you'll need to look elsewhere at much larger bags and/or combinations of bags.

In case you're wondering, I paid the Amazon-advertised price for this product. I only write reviews for items I personally use and test. Please know I did the best I could at the time I wrote this review and always welcome both constructive feedback (to make my reviews better) and all questions related to this review (to make it better and help where I can). I will try to address both as time allows, within a reasonable period from the date I posted the review. I'm a family man; so, my time isn't always my own. Thanks for understanding.