This document lists the different valve stem to gas cylinder connection threads currently and 
historically existing worldwide and provides official coded designations for them. These coded 
designations will then be available for identification and marking purposes.
It also gives guidance concerning which threads are dimensionally identical and which are 
interchangeable.
Furthermore, this document provides guidance for valving procedures when fitting valves to gas 
cylinders.nd edition 2019-05 Gas cylinders — Compilation of national and international valve stem/ gas cylinder neck threads and their identification and marking system Bouteilles à gaz — Compilation des filetages nationaux et internationaux des queues de robinets/goulots de bouteilles et leurs systèmes d'identification et de marquage Reference number ISO/TR 11364:2019(E) ？ ISO 2019 ISO/TR 11364:2019