Question about Multi BASE - 70372

I'd chose the right size according to your laptops size, so you don't carry around extra weight and size. But if you like extra size to carry around other stuff, sure go for the bigger one. Also 15.6" is just the size of the display itself. It doesn't say anything about the real dimensions of your laptop like if its a bit wider or about the thickness.

Here the dimensions of the inside, so you can

compare it with the actual size of your laptop and see if it fits and chose accordingly:

15.6" Bag = 380 x 265 x 40 mm
17.3" Bag = 420 x 295 x 45 mm