I bought this for my partners bike, she wanted to be able to carry a Litelok X3 but wanted something that looked good too. It really suits the Tuono s looks and isn t too big. The X3 fits in and also her disk lock without having to expand it, I haven t had to expand it but it looks like you could get quite a bit more in there if you wanted to. The base stays on the bike or can be unclipped and you can then get the shoulder strap out and turn it into a mini rucksack which is actually quite useful