> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tryblend.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Collection
> Load a saved collection as one reusable file bundle, selected on the node or supplied at run time.
The **Collection** node feeds the files from one saved collection into the workflow. Pick the collection directly, or connect a [User Input](/workflow/nodes/input) so the caller can select it in the Runner or API.
Those files can be images, video, audio, or any other file you've saved there. Collection is a source of file content; its only input is the saved-collection selector.
The whole collection is emitted as **one item containing multiple file parts**. It does not automatically run the next node once per file.
## Inputs
| Handle | Type | Required | Notes |
| --------------------------- | ------------ | -------- | ------------------------------------------------------------------------------------------------------- |
| Collection (`collectionId`) | `collection` | Yes | Select a saved collection on the node, or connect a User Input to let the caller choose it at run time. |
## Outputs
| Handle | Type | Notes |
| --------------- | ------ | ------------------------------------------------------------------------------ |
| `out` ("Files") | `file` | Carries the selected collection as one item with one file part per saved file. |
A Collection containing ten files is still one workflow item. A compatible downstream node receives the ten files together and runs once.
## Settings
* **Collection** — the saved collection to read. Until you pick one, the node shows **No collection**. Once selected, the badge shows its name and file count.
* **Connected collection input** — a User Input can override the saved selection for each published run.
## When to use
Reach for Collection whenever a workflow should reuse a saved set of files:
* Feed a saved set of product photos into a generation or [LLM](/workflow/nodes/llm) chain as a reusable reference set.
* Reuse the same reference images across many runs without re-uploading them each time.
* Keep the collection fixed in the workflow, or expose its selector with User Input when callers should choose among saved collections.
When callers should upload new files rather than choose a saved collection, bind User Input directly to a downstream file field.
## Connects to
The **Files** output feeds a downstream `file` target:
* A generation, [LLM](/workflow/nodes/llm), or tool parameter that accepts generic files.
* A [Batch](/workflow/nodes/batch) file row when you want Set/Explode control.
* A [Result](/workflow/nodes/result) node if the collection files themselves should be returned.
Standard connection compatibility applies. A generic `file` output does not narrow itself to an image-only, video-only, or audio-only target.
## Notes / limits
* **Emits the whole collection as one file bundle.** A Collection node does not automatically run the next node once per file. Downstream nodes receive the compatible files together.
* **Explode explicitly when needed.** Connect Files to a Batch file row and enable **Explode** to emit one item per file. Leaving the row in **Set** mode preserves the bundle.
* **An empty or unselected collection emits nothing.** If no collection is picked — or the selected one has no files — the node produces zero parts and **completes**; it does not fail the run. Downstream nodes simply receive no items.
* **Files are read for you.** During a full run the server loads the collection's files directly; in the editor, previews read the already-loaded collection contents. You don't wire up any fetch step or credentials.
* **No direct single-node run.** Collection is a source for full runs and for resolving a downstream node's inputs; it does not have its own standalone Run action.
## Next steps
Understand the difference between one item with many file parts and many separate output items.
Keep a file set together or explode it into one item per file.