# HoleFill

> The hole_fill block of a .well file: a list of HoleFill objects.

Property `hole_fill` of the .well root, an array of objects, required. [Defined in the spec](/format/spec/v2/object-schemas#holefill--hole_fill).

| Field | Type | Required | Values / constraints | Description |
| --- | --- | --- | --- | --- |
| `from` | number | yes |  |  |
| `to` | number | yes |  |  |
| `type` | string | yes | `gravel_pack`, `seal` |  |
| `diameter` | number | yes |  |  |
| `description` | string | yes |  |  |