These proprietary library files are used by Intan software to talk to the Opal Kelly board on their devices. Since the libraries are shared between a lot of software that makes use of Intan hardware, this repository exists to include the files only once.
This repository can also generate a Debian package to quickly install the libraries and have them used by other software. It can also be used to install them on any Linux distribution.
You can get a prebuilt package for Debian/Ubuntu from the GitHub releases tab. For a Windows driver installer, please refer to the Intan Download Page.
Please note that these libraries are not free software! The licensing terms allow the use of these libraries only in conjunction with Opal Kelly devices, and due to the sublicensing/distribution requirements likely only in conjunction with code that makes use of Intan hardware as well, as the Intan source code is what the libraries are distributed with:
[...] Licensee may integrate and sub-license Software for distribution but Software must only be used in conjunction with Opal Kelly devices or devices incorporating Firmware. [...]