Issue with translucent material

Hi everyone, I have a translucent material with opacity set to 1, but I have this result…Why? Can anyone help? Normals looks fine in blender.
Thanks.

Is this one or multiple meshes?

Hi, this is a single mesh but it’s the same with multiple meshes.
BTW, I need this shader to work with multiple meshes, I’m following this tutorial to create fake booleans:
UE4 | How to create a fake hole that you can move it in runtime. - YouTube