It's really not the roomiest but the new one I have now if you're needing a small one is
https://www.amazon.com/dp/B00CBT5C4C/ref=twister_B08547YT37?_encoding=UTF8&th=1
It's pretty small only because while the full dimensions register at 21inches it's more narrow than most I think but it does have an extender like normal to make it bigger. I have the two wheeled version while my husband has the 4 wheeled one but the 4 wheeled one measures larger because of the wheels, same interior space. FWIW I packed more in there than they mention. I packed a swimming suit, two sports bras, a spare bra, three dresses, pjs, shoes, shirts, underwear, socks, etc for about 3-4 days worth.
I found the tote it came with while small actually packed a decent amount of stuff in it between the front pocket and the main pocket, then the back zipper held more than I thought.
These days I won't travel without a personal item that can attach via a strap to my carry on.