[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [local‑first/Auth](https://evolu.dev/docs/api-reference/common/local-first/Auth) › WrappedDeviceSecret

```ts
type WrappedDeviceSecret = Uint8Array<ArrayBufferLike> &
  import("../Brand.ts").Brand<"Length72"> &
  import("../Brand.ts").Brand<"WrappedDeviceSecret">;
```

Defined in: [packages/common/src/local-first/Auth.ts:192](https://github.com/evoluhq/evolu/blob/aa223771feea747ffb1b0f5f3271574455633e37/packages/common/src/local-first/Auth.ts#L192)

A [DeviceSecret](https://evolu.dev/docs/api-reference/common/local-first/Auth/variables/DeviceSecret) wrapped by a key from a [DeviceSecretKeyProvider](https://evolu.dev/docs/api-reference/common/local-first/Auth/interfaces/DeviceSecretKeyProvider):
a 24-byte nonce, the 32-byte ciphertext, and its 16-byte authentication tag.
The format is permanent once shipped.