Instruction: Answer the given question using the supporting document.

Input:
Question: Can I stack this filter over my Hoya ND400?
Document: It does what a quality polarizer is supposed to do, make the skies blue and the foliage pop. I think that the Nikon' s effect is slightly stronger than the smaller Hoya 67mm Extra Thin Circular Polarizer Super Multi Coated Glass Filter that I also own. While the Hoya is excellent, I think the Nikon is slightly better. Either way, you can not go wrong.
This 5mm thin filter is made with precision and quality. You can count on pretty much any Nikon products that are made within the highest standards. I have several other brand polarizer but this one is one of the best looking ones. I've stacked this filter and 3mm Hoya ultra thin on my 12-24mm Nikkor and due to its excellent sky darkening effect can hardly notice any vignetting problems even at the shortest focal length.
Using on a Nikon D3S. I'm a Hoya user and took a chance on the Nikon thinking - it's a Nikon, it must be better!. Wrong. Terrible photographs, no clarity, loss of focus, over saturation of colors. I'll never use this again. Do yourself a favor, spend the money, stick with Hoya.
!I purchased the THIN CPL on Amazon since it should fit on to the Wide Angle lens I  plan on purchasing in the future (I will update this review when I do). If you do standardize on one size like I did at 77mm, you should get a set of metal stack caps to protect the filters while carrying them.
I'd buy again if I needed to replace it. I bought my Nikkors to last a long time and I feel the same way about this filter.
I used this filter several times and it performs just like any other Nikon product. The best part about this filter is how it reduces window and water reflections. Excellent!
As expected, the filter is well made and perfect for wide angle lenses to prevent vignetting. I would go for this filter any day over one of the aftermarket manufacturers.
I got it in time, nice, everything is OK - except I see myself in any glass surface like before. For all that I twisted the filter in all position at any 1/8 inch.
The optical quality of this filter blows away every other Polarizer I own, however why is the knurling on the edge and not the front? you can't get a grip on the damn thing when you have a hood on. And when you use a polarizer, you're in good sunlight, and need a hood.
It's the only filter I use, and I did away with stepping rings so that I could use it with my other lenses. It's constructed really well, has smooth rotation and is a delight to use. The colors it helps to bring out are surreal, yet authentic, and there are no "distortions".
Answer: I'm not much a camera tech so I can't authoritatively answer your question, but I have my polarizing filter on top of a regular daylight filter on my Nikon D40.