Thanks Isobella

the boy that I have in mind is just six and I am sure he is shorter than my son (who is about 117cm, I should check!) so we would get good use out of it. His mum is having a baby in a few weeks, and she also has a three year old so was hoping to offer to take her eldest home for her.
Just looking at the
manual I am not sure I like the look of the seatbelt for an older child?

I get DS1 to try and sit in it and see what I think.
Just be handy that can store it flat in the boot. Just wondering if you know of any other narrow boosters that might be suitable?