Specification and size (unit is cm/g) 11.6 inch outer (34cm*23cm*3cm) inner (32.5cm*21.5cm*2.5cm) 300g-400g 12.5 inch outer (34cm*23cm*3cm) inner (32.5cm*21.5cm*2.5cm) 300g-400g 13.3 inch outer (36cm*26cm*5.5cm) inner (35cm*25cm*5cm) 300g-400g 14.1 inch outer (39cm*28cm*5.5cm) inner (37.5cm*26.5cm*5cm) 400-500g 15.4 inch outer (39cm*28cm*5.5cm) inner (37.5cm*26.5cm*5cm) 400-500g 15.6 inch outer (43cm*32cm*6cm) inner (41.5cm*30.5cm*5.5cm) 400-500g (Because it is manual measurement, there may be an error of 1-2cm, it is recommended to choose a large-capacity inner bag, because you may need to store your charger or other things) Excellent protection: The materials in all laptop bags include thick foam and super soft velvet lining, including zipper edges and internal borders. The extra-thick cushions at the corners can provide 360 protection for your computer to prevent accidental scratches, bumps, bumps and impacts. The surface of the sleeve shell is made of waterproof Oxford fiber. If it is raining, it can effectively block water and steam. Don't worry about splashing or raining to wet your precious Macbook or matebook or surface . Well-organized pockets: Large space capacity, can be neatly placed charging, mouse, mobile power, mobile phone, pen, card and other accessories. and easy to carry,This messenger bag can hold screen size up to from 11.6-17 inch such 11.6 - 17.3 MacBook Pro, Dell ,Lenovo ,most Chromebook, Ultrabook ( Acer / Asus / Dell / Fujitsu / Lenovo / HP / Windows / Ipod / Netbook / Toshiba etc.),may not snugly fit all computers due to variations in the sizes of different models. Multi-application scenarios:our sleek laptop case is slim and lightweight, which is very suitable for men, women, girls or universities in business, travel, work, school and other occasions.