Through browsing this website you may have chanced upon a piece of data in the tables of information about a particular product and wondered what on earth “DN” stands for.

DN (or “Data Norm”) is a pretty simple concept, it simply shows interchangability between fittings and hoses, it is a “Nominal Width” using no particular standard measuring scale.

A banjo fitting with a barb for fitting a hose onto may have a “DN” of 6 and it’s part number will probably finish with .0600, this banjo fitting would be suitable with any hose that also has a DN of 6 and it’s part number will also finish with .0600

That’s it, simple eh!