> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ntop.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Shell

<CardGroup cols={2}>
  <Card title="Implicit Body, Scalar, Shell Enum" href="#implicit-body-scalar-shell-enum" />

  <Card title="Implicit Body, Scalar Field, Shell Enum, 5.24.0" href="#implicit-body-scalar-field-shell-enum-5240" />
</CardGroup>

***

## About this Block

**What it does:** The **Shell** block hollows out an Implicit Body with a thickened outer wall.

**Common uses:**

* Lightweighting solid parts

**Tips:**

* The wall is thickened Inward, Outward, or equally in both directions with the Center input.
* It is ideal for lightweighting, and works well when combined with the **Volume Lattice** block to fill the hollow space with lattice.
* You can vary shell thickness using a Ramp block: ([https://support.ntopology.com/hc/articles/4411539633683](https://support.ntopology.com/hc/articles/4411539633683))
* What happens if you shell a boolean union inward: ([https://support.ntopology.com/hc/articles/4403375026451](https://support.ntopology.com/hc/articles/4403375026451))

## Example File

![Shell](https://storage.googleapis.com/files-learn/static/ExtendedBlockDocs/Shell.jpg)

***

<h2 id="implicit-body-scalar-shell-enum">
  Implicit Body, Scalar, Shell Enum
</h2>

Hollow an object by offsetting inward or outward the outer surface of an implicit body.

### Inputs

| Name      | Type                                                                 | Description                                                     |
| --------- | -------------------------------------------------------------------- | --------------------------------------------------------------- |
| Body      | [Implicit Body](../../../../block-documentation/types/implicit-body) | The Implicit Body to shell.                                     |
| Thickness | [Scalar](../../../../block-documentation/types/scalar)               | The wall thickness.                                             |
| Direction | Shell Enum                                                           | The direction to thicken the body to produce the wall thickness |

### Outputs

| Type                                                                 |
| -------------------------------------------------------------------- |
| [Implicit Body](../../../../block-documentation/types/implicit-body) |

***

<h2 id="implicit-body-scalar-field-shell-enum-5240">
  Implicit Body, Scalar Field, Shell Enum, 5.24.0
</h2>

Hollow an object by offsetting inward, center, or outward from the Surface.

### Inputs

| Name      | Type                                                                 | Description                                                                       |
| --------- | -------------------------------------------------------------------- | --------------------------------------------------------------------------------- |
| Body      | [Implicit Body](../../../../block-documentation/types/implicit-body) | Body to Shell                                                                     |
| Thickness | [Scalar Field](../../../../block-documentation/types/scalar-field)   | Wall thickness to offset by. Negative values will shell in the reverse direction. |
| Direction | Shell Enum                                                           | Direction to Shell the body.                                                      |

### Outputs

| Type                                                                 |
| -------------------------------------------------------------------- |
| [Implicit Body](../../../../block-documentation/types/implicit-body) |