> For the complete documentation index, see [llms.txt](https://athome-1.gitbook.io/athome-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://athome-1.gitbook.io/athome-docs/assets/sim.md). # SIM A `SIM (Subscriber Identity Module)` represents a SIM card used in mobile equipment such as telephones, tablets, 4G/5G modems, etc. You can manage these SIM cards as specific objects to track their use and allocation. {% hint style="success" %} Note that if you modify a field manually, it will be considered locked. This will prevent it from being modified the next time the automatic inventory is uploaded. For more information, see [lock](https://github.com/glpi-network/gitbook/blob/develop/manual/modules/assets/broken-reference/README.md) {% endhint %} In a display form, the following information is available: ![Detail view SIM](https://2965217165-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FBk8u0TPogHtiUd7DaQyf%2Fuploads%2Fgit-blob-c831db4903d2cdb8bdd116dbc5ccee9e7993185a%2FSIM.png?alt=media) * Code PIN * Code PIN2 * Code PUK * Code PUK2 * [Line](/athome-docs/management/lines.md) * Mobile Subscriber Identification Number (MSIN is last 8 or 10 digits of IMSI) * [Serial number](/athome-docs/tabs/common_fields/serial_number.md) * [Inventory number](/athome-docs/tabs/common_fields/inventory_number.md) * [Location](/athome-docs/tabs/common_fields/location.md) * [Status](/athome-docs/tabs/common_fields/status.md) * [User](/athome-docs/tabs/common_fields/user.md) * [Group](/athome-docs/tabs/common_fields/group.md) * [Comments](/athome-docs/tabs/common_fields/comments.md) *** ## Management Management of financial and administrative information, this information is visible in the 'Management' tab on the computer's form. Go to Financial & administrative information *** ## Documents The document tab lets you link different types of file to a material (PDF, txt, png, etc.) You can attach a document already uploaded to GLPI or add a new one directly from this tab. Go to Documents *** ## Locks Locks are used to prevent a field from being modified when the inventory is uploaded. You can lock/unlock the fields you wish in a GLPI object. Go to Locks *** ## Contracts GLPI supports contracts management, in order to manage contract types such as loan, maintenance, support... Contracts management allows to: * make an inventory of all contracts related to the organization assets * integrate contracts in GLPI financial management * anticipate and follow contract renewal. * Documents The [document](/athome-docs/management/documents.md) tab lets you link different types of file to a material (PDF, txt, png, etc.) You can attach a document already uploaded to GLPI or add a new one directly from this tab. Go to Contacts *** ## History The *History* tab is used to show any changes made to an item. The following information about the changes is available: * ID of the change. * Date and time the change was made. * User who made the change. If this field is not filled, it means that the action was done automatically (For example: automatic inventory update). * Field that was changed. * Description of the change that was made. The description of the change represents either the difference between the old and the new value (For example with location field: Change HQ to Remote Office A), or the explanation of the action which was carried out (For example: Uninstallation of a software: "Gimp 2.0"). {% hint style="info" %} For dropdowns or objects with a parent/child relationship, the modification of a child will appear in the history of the parent element. {% endhint %} *** ## All Information For an item, all information is displayed on one page from the *All* tab. This shows all of the tabs of an object's form in one view, one below the other.