The DIN 45 thread, derived by the Deutsches Institute for Normung e.V. (“DIN”) - the German Institute for Standardization), is a 45mm standardized thread more commonly found on jerricans and carboys in EU member states and Asia.

A quirk of the DIN 45 thread is that a GL45 cap will usually fit onto it, although the GL45 cap is usually too deep to seal properly.  By removing a bit of height from a GL45 cap, it’s possible to use a GL45 on DIN 45 - one advantage being   the many color options available in GL45.  However, the converse does not work: DIN 45 caps won’t typically fit a GL45 bottle.