Does anyone have any modular luggage/suitcases?

[KatyMac]

So a smaller size that you can add on to? Or zip together or something?

Years ago I went backpacking through Asia. I bought a massive rucksack that had a smaller day use rucksack zipped onto it.

I was thinking something like this

A rucksack wouldn't be my first choice but maybe I should have a look

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