I've long been a user of seat packs for touring, but decided to get something light for road biking - and this hits the sweet spot! No need for a mini-pump as one flat is all you should see, so a 16g CO2 is good. I carry a butyl tube that fits 28-32 mm tires (I use Aerothan, but do not want it for a road-side fix), a Lezyne Trigger Drive and a narrow Topeak Mini 9 Pro (from which I removed the supplied tire levers), plus two normal tire levers. There is room for credit cards, cash, etc. As someone else mentioned, a Mattone XL that is 15 mm longer and wider would hit the sweet spot for touring and mtn bikes, ie allowing for a bigger tube and a 25mm CO2 cartridge.
People say this pack is small - which is true - but you can still pack a surprising amount of gear in it if you pick carefully. I keep a tube, Crank Brothers F15 multitool, folding SwissTech pliers, one CO2 cartridge, tire levers, patches, glue, master link, oil, pedal spike, tire boot and a small light for night repairs. Normally I don't use Tubolito tubes but I have one in here because it's very compact. My inflator detaches from the Blackburn CO2'fer pump, so that conserves space. The pack is very well made and extremely secure.
This is a wonderful Seat Pack. I like it better than any other and I have been riding bikes and using Seat Bags for 30+ years. It has a great zipper so you can get a lot in without worrying about breaking it. I am carrying everything I need for my road rides Including tubes, tire levers, tools and extra chain links and patches. I really love this product.
I've had many bicycle seat packs. This one is just the one I needed for one of my road bikes. It is well made and waterproof. It is just the right size of a multitool, tire levers, tube, CO2 cartridge, ID, and a gel. The BOA attachment is great and makes it "easy on & easy off"! David