# Product structure

OS Open Roads consists of three core features:

* **RoadLink** – A feature which represents all or part of a road.
* **RoadNode** – A feature which represents the end of the network, a change in attribution, or a junction.
* **MotorwayJunction** – A feature which provides junction information along roads classified as a Motorway.

Features are provided as a FeatureCollection.

This product was built with the INSPIRE Transport Networks Data Specification as a basis, which results in the product inheriting attribution from INSPIRE. An overview of the product structure is detailed below, which highlights the inherited INSPIRE feature types and attribution. Note that properties of the INSPIRE specification which are voidable are not included in the image below or the subsequent tables. For information on the INSPIRE properties omitted from this product, please see the [INSPIRE Transport Networks Data Specification](https://knowledge-base.inspire.ec.europa.eu/index_en).

{% hint style="info" %}

### Attribute naming across formats

GML attribute naming is used in the main text of this guide. GeoPackage and vector tile attribute naming is very similar to GML as there are no character-length limitations in the GML, GeoPackage or MBTiles formats; however, shapefile attribute naming is different due to the 11-character limit for attribute names in the shapefile format. 

Attribute mappings between the formats are provided in the following pages:

* [Esri shapefile overview](/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/esri-shapefile-overview.md)
* [GeoPackage overview](/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/geopackage-overview.md)
* [Vector tiles overview](/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/vector-tiles-overview.md)
  {% endhint %}

<figure><img src="/files/4BOS4dRToNnKjFw8931z" alt="UML diagram illustrating the data structure of OS Open Roads and how it has been extended from the INSPIRE Transport Networks Data Specification." width="563"><figcaption><p>UML diagram illustrating the data structure of OS Open Roads and how it has been extended from the INSPIRE Transport Networks Data Specification.</p></figcaption></figure>

The individual feature types and code lists within this UML diagram are explained in detail in the feature types and code lists pages.


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