# Product supply

## System requirements <a href="#id-1.4-system-requirements" id="id-1.4-system-requirements"></a>

OS MasterMap Topography Layer data is designed for use as a digital map within GIS and database systems.

For details of Ordnance Survey’s Licensed Partners who can incorporate OS MasterMap Topography Layer in their systems, please see the [Our Partners page on the OS website](https://www.ordnancesurvey.co.uk/business-government/our-partners).

Ordnance Survey does not recommend either suppliers or software products. The most appropriate system will depend on many factors, such as the amount of data being taken, resources available within the organisation, the existing and planned information technology infrastructure or, last but by no means least, the applications in which OS MasterMap Topography Layer is to be used.

However, as a minimum, the following elements will be required in any system:

* A means of reading the data in its native format, or translating the data into a file format, or storing the data in a database.
* A means of storing and distributing the data, perhaps in a database or through a web-based service.
* A way of visualising and querying the data, typically a GIS.

Please see the [Product supply mechanism and options page](/os-downloads/products/maps-and-imagery-portfolio/os-mastermap-topography-layer/os-mastermap-topography-layer-overview/product-supply/product-supply-mechanism-and-options.md) for more information on handling the product.

## Available formats for the product <a href="#id-4.1-available-formats-for-the-product" id="id-4.1-available-formats-for-the-product"></a>

* GeoPackage
* Vector tiles (MBTiles)
* Geography Markup Language (GML) 2.1.2

## Coverage <a href="#id-4.2-coverage" id="id-4.2-coverage"></a>

Coverage is Great Britain (GB).

## File size <a href="#id-4.3-file-size" id="id-4.3-file-size"></a>

File sizes vary greatly depending on tile size and the quantity of features present in a tile:

* GeoPackage 25km² tile range: Varies (dependent on AOI selection)
* Vector tile GB Supply: Approx. 20GB
* GML 25km² tile range: Varies (dependent on AOI selection)
* GML GB Supply: Approx. 47GB

## Product update schedule <a href="#id-4.4-product-update-schedule" id="id-4.4-product-update-schedule"></a>

OS MasterMap Topography Layer is updated every 6 weeks. Information about the current product version, and information about future and past releases, can be found on the [Product Refresh Dates page](/os-downloads/resources/product-resources/product-refresh-dates.md#os-mastermap-topography-layer).


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.os.uk/os-downloads/products/maps-and-imagery-portfolio/os-mastermap-topography-layer/os-mastermap-topography-layer-overview/product-supply.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.