The first four digits of the NATO size refer to the user’s height, and the last four digits to chest circumference. For example, 7585 means 175-185 cm (5' 9" - 6' 1") and 0510 is abbreviated from 105-110 cm (41.4" - 43.5"). We’ve written this out next to the sizes for easier reading.

The height range is very large for some reason. In our opinion the 160-180 cm (5' 3" - 5' 11") shirt is more suitable on a 175-180 cm (5' 9" - 5' 11") wearer, so choose a size where you're in the upper third of the suggested range. Obviously, our arms vary in length and people have different tastes about sleeve length.

The sizes are generous enough that your chest measurement can – most likely – comfortably exceed the listed size without issue. For instance, the 9095 chest size shirts fit snugly on someone with a 120 cm / 47" chest – though there was a bit of tightness under the arms. The torso is uniformly cut, meaning it’s about the same size around the chest as it is around the waist. The hem is about 5 cm / 2" longer in the back than in the front.

The following table is a rough conversion guide.