> For the complete documentation index, see [llms.txt](https://frinn.gitbook.io/custom-machinery-1.21/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://frinn.gitbook.io/custom-machinery-1.21/creating-custom-machines/machine-gui/empty-element.md).

# Empty element

An element that renders nothing

The empty gui element does nothing on it's own, it's useless to add it in a machine json.

It's only use is for replacing another gui element when a recipe is processing, that way it is possible to 'remove' a machine gui element by replacing it by an empty element with the same id.

Empty elements are defined in json with : `"type": "custommachinery:empty"`.

### Properties

The empty element has 1 mandatory property and 1 optional property : 

#### Mandatory property

```json5
"type": "custommachinery:empty" //Mandatory to define an empty element.
```

#### Optional property

<details>

<summary>Id</summary>

#### Name : `id`

#### Description :&#x20;

The id of the element.

If used in a custom machine recipe, this element will replace another element with the same id.

#### Example :&#x20;

The element will replace another element with the id "input".

```json5
"id": "input"
```

</details>

### Example

A simple empty gui element :&#x20;

```json
{
    "type": "custommachinery:empty",
    "id": "input"
}
```