Milling machine vacuum nozzle

Another day, another nozzle! Lots of vacuum nozzles on the Thingiverse, but all the ones I've seen have one major flaw - no dimensions specified in the description. Specifically the width of the tip.

My milling machine has 14mm T-slots, and standard nozzle doesn't fit. This nozzle has a 12mm wide tip, and is intended for vacuum hoses that have the diameter at the tip of approximately 30mm.