# extra_signatures_op · FT4 Rell API · Chromia Docs (concept)

> operation extra_ signatures_ op(signers: list<byte_ array>) 

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/tests.operations.auth/extra_signatures_op/

OPERATION

# extra\_signatures\_op

```signature
operation extra_signatures_op(signers: list<byte_array>)
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/tests/operations/auth.rell#lines-61)

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/tests.operations.auth/extra_signatures_op.html)Generated API reference, mirrored from the live docs