# Job: Restack Particles

<figure><img src="https://1916621962-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M7DGv3GkRvGGpbVPCgg%2Fuploads%2Fp3wUGEWWCQV8JIh4EsAu%2Fv4.1.2-restack-particles-1.png?alt=media&#x26;token=e3eb4ed8-3e4a-4163-9527-421aac89ef40" alt=""><figcaption><p>Input particles can be distributed across many .mrc files, and often only a subset of each file is being used for downstream operations. Restack will consolidate the particles from many files into a smaller number of files that don’t include unused particles, therefore taking up less disk space.</p></figcaption></figure>

## Description

Re-write input particles to new consolidated output particle files. Restack Particles is useful for filtering unused particles from`.mrc` files, can speed up caching, and helps with data management. Restacking will not change results of downstream processing.

During particle data processing, particles are distributed across many particle `.mrc` files (typically one file per micrograph from extraction) and usually only a subset of all extracted particles will be used downstream. Restack Particles will read, consolidate and write out particle data into new files - allowing the original particle files, which also include unused particles, to be removed. This process also usually results in particles being aggregated into a smaller number of larger files, speeding up filesystem operations including caching performance.

## Input

* Particles

## Common parameters

* `Particle batch size:` number of particles that will be written per output file
* `Save results in 16-bit floating point:` Saves the output particles in [float16 format](https://guide.cryosparc.com/processing-data/tutorials-and-case-studies/tutorial-float16-support) (CryoSPARC v4.4+).

## Output

* Restacked particles

## Common Next Steps

* Running 2D Classification, 3D Classification, 3D Variability Analysis or Heterogeneous Refinement on restacked particles
* Clearing the particle extraction job(s) that produced the input particles to save storage space