Download File Ultra7z_zip_optimizer_1.05.zip -

: The developer strongly recommends creating a backup copy of your files before using the optimizer, as it modifies the archive.

: "Ultra" compression levels generally require significant CPU and memory resources to achieve their high ratios. Download File Ultra7z_ZIP_Optimizer_1.05.zip

For standard file compression without third-party optimizers, you can use the official 7-Zip website to download the latest stable version of the core archiver. Ultra7z Optimizer - auto Lzma/Ppmd/Deflate : The developer strongly recommends creating a backup