Two reasons. Your laptop does not always travel in that bag, and a sleeve means it is protected in a tote, a duffel or a hand carry as well. And a sleeve protects against the things padding does not: keys, a bottle and a charger sharing the compartment, or the laptop being slid across a desk on its own.

Plenty of people do, and it is a sensible habit. Inside a backpack the sleeve stops your laptop rubbing against whatever else is in there, and it means you can pull the machine out and set it down without putting it directly on a wet cafe table. In a bag with no padded section, it is doing the protecting.

It comes as one size. We know that is the first thing you want pinned down, so if your laptop is at the larger end of 15 or 16 inches, check the measurements on the product page before you order rather than assuming. For a standard 13 or 14 inch machine it is the straightforward choice.

It is padded, which is the part that matters, and made from recycled canvas rather than a thin fabric wrap. It is designed to absorb the knocks and scrapes of daily carry inside another bag. It is not a hard case, so it will not protect a laptop from being dropped down a flight of stairs, and nothing at this size would.

Often exactly. The prints here also run across the bags, so mini leopard, navy polka dot and heart print all appear on backpacks and crossbody styles too. Matching a sleeve to the bag it lives inside is quietly satisfying, and clashing the two on purpose is more in keeping with how we use colour.