This package works with the “google cardboard” for UNITY that must be downloaded first using the following link:
https://developers.google.com/cardboard/unity/?hl=en

Version needed Cardboard SDK=0.8

Check out the details from the Unity Asset Store: https://assetstore.unity.com/packages/tools/gui/cardboard-vr-touchless-menu-trigger-58897

Now download Cardboard VR TouchLess Menu Trigger FREE Unity