> For the complete documentation index, see [llms.txt](https://docs.31third.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.31third.com/protocol/overview.md).

# Overview

The 31Third batch trade smart contracts enable the execution of multiple transactions together as one bundle and collect a configurable fee in basis points of the receiving currency of the trade. The current implementation supports the following:

* Trades through 0xExchangeProxy ([`0xDef1C0ded9bec7F1a1670819833240f027b25EfF`](https://etherscan.io/address/0xDef1C0ded9bec7F1a1670819833240f027b25EfF))
* Wrapping/Unwrapping (W)ETH ([`0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2`](https://etherscan.io/address/0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2))

## Architecture

For easily integrating with other liquidity sources, such as Aave, Curve, Balancer, and more in the future, the contracts utilize the adapter pattern and register the concrete implementations in a registry. The architecture can be seen in the following diagram:

<figure><img src="https://4016215624-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fv7J8JT3jWVuE9GqVdGGn%2Fuploads%2FV6ZvT4KdG4zbxLoa89Fk%2Fbatch-trade-architecture.png?alt=media&amp;token=97eceb76-c2b0-4708-b6bd-4fd05c667bfa" alt=""><figcaption><p>Contract architecture</p></figcaption></figure>