UnzipOne 4.0.6 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. UnzipOne for Mac lies within System Tools, more precisely File Compression. We recommend checking the downloaded files with any free antivirus. This free Mac app was originally created by Trend Micro Inc.
From the developer:
Unzip One can open and extract archive files including RAR, Zip, 7z, gzip, bzip2, ISO and more fast and easily. All common archive formats are supported. You can secure the extraction to protect against viruses distributed in compressed files. You can preview your files directly without extracting them. Also, the tool lets you compress files with password and high-level encryption.
You may want to check out more Mac applications, such as YemuZip, xACT or DropDMG, which might be related to UnzipOne.