# AddressBase Plus Islands Technical Specification

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This product was designed to allow current customers of AddressBase Plus to add this product (AddressBase Plus Islands) to their current data holdings. This means there are columns in the schema of this product which will never be populated. These are identified on the appropriate pages throughout this specification document.
{% endhint %}

This technical specification includes the following sections:

* [Data formats](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/data-formats)
* [Supply and update](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/supply-and-update)
* [AddressBase Plus Islands structure](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-premium-islands/addressbase-premium-islands-technical-specification/addressbase-premium-islands-structure)
* [Feature types](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/feature-types)
* [Code lists and enumerations](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/code-lists-and-enumerations)
* [CSV to GML mapping](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/csv-to-gml-mapping)
* [Example records](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/example-records)

## AddressBase fundamentals 

Additional documentation covering the complete family of AddressBase products is available in the AddressBase Fundamentals pages. These covers key elements of design for AddressBase products, including:

* [Future and past publication dates](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/future-and-past-publication-dates)
* [Unique Property Reference Number (UPRN)](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/unique-property-reference-number-uprn)
* [Coordinate reference systems](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/coordinate-reference-systems)
* [Classification scheme](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/classification-scheme)
* [Data sources](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/data-sources)
* [Street names and numbering](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/street-names-and-numbering)
* [Currency completeness and precision](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-core/addressbase-core-overview/currency-completeness-and-precision)
* [Product supply](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/product-supply)
* [AddressBase local custodian codes](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/addressbase-local-custodian-codes)
* [AddressBase Islands local custodian codes](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/addressbase-islands-local-custodian-codes)


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