API Reference > imodeljs-backend > ElementAspects ElementAspects Subclasses of ElementAspects. See the learning articles. Classes Name Description ChannelRootAspect A ChannelRootAspect identifies an Element as the root of a channel which is a subset of the overall iModel hierarchy that is independently maintained. ElementAspect An Element Aspect is a class that defines a set of properties that are related to (and owned by) a single element. ElementMultiAspect An Element Multi-Aspect is an ElementAspect where there can be n instances of the Element Aspect class per Element. ElementUniqueAspect An Element Unique Aspect is an ElementAspect where there can be only zero or one instance of the Element Aspect class per Element. ExternalSourceAspect An ElementMultiAspect that stores synchronization information for an Element originating from an external source. Interfaces Name Description OnAspectArg Argument for the ElementAspect.onXxx static methods Beta OnAspectIdArg Argument for the ElementAspect.onXxx static methods that only supply the Id of the affected aspect. Beta OnAspectPropsArg Argument for the ElementAspect.onXxx static methods that supply the properties of an aspect to be inserted or updated. Beta Namespaces Name Description ExternalSourceAspect Last Updated: 29 November, 2022