# Version 2 Contract Enhancements ERC404 has already undergone its first major upgrade citing significant enhancements. The ERC404 protocol version 2.0-beta introduces significant updates to improve functionality and efficiency. Notably, it adopts a FIFO queue for ERC-721 token IDs, enhancing predictability and reusability, aligning with typical NFT collection behaviors. Full ERC-20 token transfers now also move associated ERC-721 tokens directly, streamlining asset management. The update brings clearer event emissions, dedicated functions for balance and supply queries, optional fixed supply cap, simplified transfer logic, and a more user-friendly minting function. Additionally, it incorporates EIP-2612 for permit approvals and EIP-165 support, alongside optimizations for gas savings. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.davinci.wtf/get-to-know-erc404/version-2-contract-enhancements.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.