SILCASILCA Mattone Under Seat Bag for Bicylces with Zipper and Waterproof zipper and BOA mounting system (Small, Black)

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.

Excellent. Holds a lot. Snugs up nicely under seat. Easy to put on and take off.

This is the perfect bag for me. Tucks tight under the seat and BOA strap mechanism, is sweet!, keeps it secure on rough terrain. I have a competitors with a hard case. Problem is after a few months of riding the clip mechanism is very wobbly. Not this bad boy, not going anywhere. As others have said it’s small. I use it for a multi tool, keys to my vehicle and ID. I run tubeless so just carry a few basics. Highly recommend, a bit pricey. Would like to see it in the $35 range.

Top quality and great BOA closure. What do I fit in this thing? For the record, this is not a large saddle bag and you need to consider what you need to carry with you. I have a CO2 cartridge and inflator, small multi tool, tire levers, tube patches, and 2 TPU inner tubes. All of this fits tightly but well with just a bit of extra room for keys etc. if I wish to put them in the bag. Note, if you use standard rubber inner tubes, it will be tight to fit one tube and all the tools I have listed, but will work.

It is roughly the size of a brick (minimalists beware). The overall quality is very good and the boa closure is excellent. I would highly recommend the bag for a person wanting to carry the “essentials” in case of a flat or mechanical. I like to use saddle bags to carry items when I flat, need to adjust seat post or gears. I do not use saddle bags to carry nutrition, I.e. gels and gummies, because of the inconvenience of getting off the bike to access them. I use my easily accessible jersey pockets to carry my nutrition. I am able to fit a 25c conti ultralite tube, CO2 canister with small chuck, and a Pedro’s multi tool including pedros small tire levers. Gravel cyclists who want larger tubes and other items will have a hard time fitting more into the bag. It secures firmly to the saddle and I do not experience rattling or “swaying” of the bag. Accessing the bag is a minor hindrance. People who want to regularly access the bag may not like having to fiddle with the boa AND zipper to access the contents. For those who use saddle bags for flats or mechanical items, this bag is an excellent option.

I have been searching for something that fits on my TT bike under my rear seat hydration. This is nearly the bag to do it but the strap is just slightly too short. finding a bigger strap is a potential solution but this strap is so nice it would be a shame to replace it. I can get it around my seat tube but it likely wouldn't stay as it is in the picture. definitely keeping it for my other bike because the bag itself feels like a great durable material with plenty of room for tube, tire levers, CO2, any essentials as expected.

Great bag, fits nicely under the saddle. Fits small pump, tube, ID/money, tool, maybe some gels. I would say its not meant for constant taking on/off. More of a set it and forget it and hope you don't have to deal with flats that often. Small and aero and doesn't look stupid.

Great bag. Perfect size, ease of installation and fits perfectly.