Downloading DeviceShelf 1.7 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. The software lies within Internet & Network Tools, more precisely Network tools. We recommend checking the downloaded files with any free antivirus. This Mac app was originally developed by Christof Müller.
From the developer:
DeviceShelf scans your local network and tells you what every device is - vendor, type, OS fingerprint, open ports - with a per-device security report and live monitoring for new or offline devices. It runs on your machine: no account, no telemetry, your network data stays local unless you enable an optional online lookup. Optional AI device ID is bring-your-own-key.
You may want to check out more software for Mac, such as attach, which might be similar to DeviceShelf.