Once downloaded, you need to "extract" the files to use them:
If an email has several attachments, some services will automatically bundle them into a single ZIP folder for you to download at once. Download Mail Brutes zip
Searching for "Mail Brutes" often leads to tools associated with credential stuffing or "brute-forcing" email accounts. Please be aware that using software for unauthorized access to accounts is illegal and violates most terms of service. Once downloaded, you need to "extract" the files