SILCA Mattone Bike Saddle Bag - .5L Capacity - Compact Under Seat Bicycle Bag for Road, Gravel, and Mountain Bikes - Easy to Access, Secure, and Durable - BOA Closure & Waterproof Zipper

Great and compact under-seat bag that holds a lot! Fits a standard 700c spare, CO2 cartridge w/ adapter, Crank Bros M17, Dynaplug Racer, and two tire levers. Quite a bit for such a small form! It's not completely waterproof, so if you take it on a wet ride, don't forget to remove anything that might rust or get ruined and dry it all out. Great zipper, BOA is money, bag sits tight and secure. Would buy again.

Fits on my Trek Verve well and has enough space in it for a multi tool, new tube, and tire levers. Doesn’t get in the way of my rear safety light too and it snug without moving. Love the quality, the look is minimal, and it’s been good for all my rides for over a year. Highly recommended it.

Great bag. Easy to transfer from one bike to the other. Doesn’t get in the way while riding and is held securely with a BOA fastener. Excellent workmanship.

Great bag with an ideal size, secured by a solid BOA dial, offering just enough room for essentials. The locking system is simple to install and stays snug against the saddle without any wobbling or shifting. Additionally, this bag looks great! Keep in mind, you'll need to remove the entire bag to access the zipper and contents, but since frequent access isn't expected (hopefully), this isn't a major issue.

I was conflicted by all of the reviews on the two sizes of this bag, so I ordered them both. They run a 700 x 30 tire. My current set up is tubeless, but I need to carry a tube just in case. When I attempted to put my 30 MM tube into the smaller size, it basically took up 90% of the space. There is no way on earth. Anybody is putting a larger tube in that small pack and putting much else in there. I just want you to be aware when you see the demonstrations and people talking about tubes, just assume most people are running smaller tubes probably 23 or 25 mm. The good news is that the larger pack is not really that big. I was able to put my tube, two CO2 cartridges, multi tool, tire, levers, and a few other things. It is very compact and sit nicely up under the seat. Sitting high under the sea, it was my other requirement for a new bag. I have been using a Garmin Varia radar detector off my seat post, and so many of the bags tend to fall down or slide down on top of it. This bag is extremely compact, and really fits and locks and placed nicely. I would highly recommend it, but just beware of the size as I think it’s a little misleading, and thus, the four stars.

This fits up tight against the seat allowing more room to attach a light to the seat post. The bag holds what I need. I have the large size for my gravel bike and the standard size for my road bike. The build quality is solid and much better than the seat bags that I’ve used for decades. I would absolutely recommend this Silva bag. It’s pricey but I’m riding bikes that cost thousands. This bag costs less than one tire and hopefully will last several years of use.

Great saddle bag that is big enough to hold the essentials. Was easy to fit and the material is not thick but seem durable

What a spectacular saddle bag! It holds exactly what I need, it tucks way neatly under the saddle, and the Boa retaining system is genius; far superior to velcro in every way. it takes a bit of thought to get it threaded properly under the saddle, but once there it essentially disappears until you need it. I got the GRANDE size because I like to carry two extra Butyl tubes with me (I know, the weight weenies will cry “TPU!” but for emergencies, I’ll take what I know works over a few grams saved, TYVM). Simply the best saddle bag I have ever used.