Packing cubes organize existing space
Three cubes can divide clothing into useful groups, but they do not add capacity to the backpack. Their size and shape determine whether they work with your own packing habits. Check whether the included set leaves room for toiletries, footwear and your computer equipment, especially if you plan to replace one cube with a rigid item.
Forty liters does not settle airline fit
A volume figure cannot tell you whether a full pack meets a particular under-seat or cabin-bag allowance. Obtain external dimensions and compare the actual packed depth with your fare’s rules. The title’s approval wording should not substitute for that comparison, and any weather-protection requirement needs construction details beyond the word waterproof.
