Yes it fits in my Hoya 77mm but I would not recommend you try it.
The shape of the wide angle adaptor almost overlaps the front of the polariser - the bit that twists. I'll
try and explain why thats a potential big problem
When you attach the two together, you need to hold both sides of the polariser else the Wide Angle Adapter will just rotate the front side and not screw into the thread.
If you can successfully get the polariser and adapter together, you will find the as the thread pulled both items together - the grip you had on both sides of the polariser is minimised by every degree of rotation. I almost twisted it in so far that I couldn't grip the front of the polariser as it was buried in the backend/body of the adaptor.
As you know the polariser is in two parts - hence holding both parts to screw it on earlier.
So what I was almost left with as a freely rotating (rearend) polariser stuck in the adaptor. You can't get to the polariser front as there is very little to grip as it has been screwed inside the adaptor frame. Elastic bands, marrigolds, mouse mats or strap wrenches ain't gonna undo that if it is too far!!!
Sorry for the convoluted reply but its soo easy to do and its too late once you realise it - a classic facepalm awaiting.
Andy