Unity 8.Oct.2021 Unfortunately, NVIDIA FleX for Unity (1.0 BETA) is no longer available.

[laserMelon]

The following assets have been deleted from the asset store.

• NVIDIA FleX for Unity (1.0 BETA)
• NVIDIA FleX Unity Plugin Samples (1.0 Beta)

Also, the publisher page has been deleted.

The "NVIDIA FleX for Unity (1.0 BETA)" page says:
Also, the "NVIDIA FleX Unity Plugin Samples (1.0 Beta)" page says almost the same thing.

Unfortunately, NVIDIA FleX for Unity (1.0 BETA) is no longer available.
This package has been deprecated from the Asset Store. This means that new purchases of the package are not allowed and that only users who already purchased or downloaded the package before it was deprecated, are allowed to download it.
In most cases, package deprecation happens because the publisher is unable or unwilling to support the package anymore. We suggest looking for alternative packages or contacting the publisher directly.
If you've already purchased it and need to download a copy, you can do so here.

[DrQwertySilence]

I think it doesn't make sense to support it because Flex was integrated in PhysX 5. Unity is build on the PhysX3.3 SDK. What do we do now? hahaha

Edit: Maybe this project should be the one to be upgraded to support PhysX 5 (Link).

[Nolram12345]

Unity is currently on PhysX 4 as far as I know. Phys 5 is currently more or less being held hostage in Omniverse by Nvidia, so we can only wait and see whether they will release it as an SDK later on it.

[rv3Dcv]

Does someone still have the Unity Plug-in? I need it for a research project and would really appreciate if someone could send it.

[korzen]

There is an unofficial paid Flex wrapper for Unity3D called uFlex

[Sevforev]

Anyone got the package? I'd be ready thankful if someone could share it.

[coolcatcoder]

For people who still want this plugin feel free to grab it from https://github.com/Tespinen/nvidia-flex-for-unity

Although personally i would recommend using clangsharp to interact with nvidia flex in unity!

[rv3Dcv]

@Tespinen Thank you for uploading! Although I personally don't need it anymore, I hope this will help others!

[Sevforev]

I'm glad to help 🙂