Big enough for having some tools and a tiny first aid kit. But it can hold all you need. Recomended to carry all the stuff for the bike in a convenient way.
the kit is well stocked and complete with all the tools you need when cycling, unfortunately the size of the case is larger than a standard bottle holder, so it doesn't fit (the photo in the presentation of the product seems in fact photoshopped). the zipper of the case, sewn backwards, compared to the photos of the presentation, it does not allow you to insert the case into the bottle holder even by pushing hard.