700x18-25 tube with a 42mm stem, at least I'm pretty sure that's what it was until the bloody thing fell off in the rain last week!

valve lenght = long

Can't recall exact length and do not have to hand to measure. It is not uber long so wont fit really deep section carbon rims, but not annoyingly short either. I have moderately deep Fulcrum rims and it is OK.

road is 23c valve lenght is long and valve is presta

mtb is standard mtb inner tube and standard valve

Presta 18-23

700 x 25-32 from memory no idea as to valve length

700c and 52mm

The product comes with a road tube, tightly folded and bound, and two small flat levers. I filled the remaining space with a small pack of glueless patches and a single allen key. A cross tube would likely be too wide to then allow the pack to zip up, and I couldn't find a multitool small enough to fit (hence the single allen key - although I'm sure I could squeeze in another key if I needed to).

Ive not tried it but i would think not. Space is tight in the bag and a multitool may just be too much - depends which multitool of course....!

I haven't tried to fit a tube and small multi tool but I feel it will be a tight fit if you had to try to fit both in the saddle bag

It should be able to- depending on the size of the multitool

I would think so have not tried yet

Probably. It holds a standard road tube with space left, plus I have a multi tool in there as well.