SysML1.0: 9.3.2.6 ItemFlow:

'.. In addition, if there is an item property (corresponds to the conveyed classifier), then one can label the item flow with the item property. For example, a label of “liquid: Water” would imply that the item flow relays Water and this relay is associated with an item property “liquid” of the item flow, i.e., the “liquid” item property is set once Water is relayed.'

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