Peak Design Packing Cube, Small
A small, weatherproof packing cube with a tear-away opening, an adjustable internal divider and an expansion/compression zip.
Eagle Creek
Three lightweight, water-resistant packing cubes in extra-small, small and medium, made from recycled fabric.
Carry-on packers who want the lightest possible way to separate clothes, underwear and accessories.
People who want to compress a bulky load: these are semi-structured organizers, not compression cubes.
The listing gives the three sizes and capacities above and says the cubes keep clean clothes separate from dirty laundry. The total capacity of the set is about 11 L, which is the useful number when you compare it with a carry-on bag.

Packing cube sizes are confusing because every brand labels them differently. Compare real volumes in litres for two popular options and plan a carry-on with a six-slide carousel.

A "pack with me" video that shows a two-week carry-on built from packing cubes, with the real cube sizes on screen and a light-versus-flexible comparison.
A small, weatherproof packing cube with a tear-away opening, an adjustable internal divider and an expansion/compression zip.