Here is the 2nd HDRIs pack. In 12K format with impressive studio quality and FREE!This pack contains 6 12K skies in EXR format.

Compatible with most 3D applications, including: Cinema 4D (requires HDRI Link or HDRI Studio Rig) Autodesk (Maya & 3DS Max) Element 3D for After Effects Houdini Blender Keyshot Other programs that accept EXR Crisp sun shadows

If you like this pack, the first contains 6 premium HDRI maps (and 12k):https://www.cgtrader.com/3d-models/textures/natural/hdri-skies-12k