I’ve got two laptops (or maybe one of them counts as a tablet?), a ThinkPad X1 Carbon and a Surface Pro 4. One’s 13.3 inches, the other 12.5. I’d been using a plain leather sleeve, but after a year it had gone all loose, so I decided to swap it out. Then I spotted these Xiaomi ones, and it just so happens Xiaomi makes laptop sleeves in two sizes too: