Celestron

Its more a photographic tool. You can use it visually but its not very satisfying because you see an obstruction on the outside and the image is more concentrated and therefore brighter which affects the visual surface contrast

It is possible but this would require to put a center "ring.mark" onto the secondary mirror.
In the beginning of this product we planned to provide the necessary ringshaped sticker plus instructions, but we had to learn that the procedure is too difficult for most people, so we gave up on promoting the laser colli for this optical system

We do have Adjustable pin type face wrench ø 2mm, # 2450062, but it will not fit into this adapter. However, there are several manufacturers of tools to open and repair camera lenses - with these keywords or "Camera Lens repair tool", you should easily find a suitable tool to reach these holes.

Of course, we will gladly sell you such a UV/IR-cut-filter. It doesn't do any harm, as long as it is of good quality and doesn't cause reflexions.
Such a filter may even be a wise choice if you decide to use the prism with ND-filters by other manufacturers, where you don't know if they let UV/IR pass or not. However, if you use our included filters, they do not only dim the visible light, but also block the remaining UV/IR.

At f/10 or even with the 0.7x reducer, you do not need the highspeed filters, the regular filters will work better. To deal with the steeper light cone at faster f/ratios, the filters need to be pre-shifted, so that a ilter for f/2 needs to be different from a filter for f/3 and from one for f/4 or slower.
Please take a look at our filter selector at
https://www.baader-planetarium.com/en/baader-narrowband-highspeed-filter-selector/
and this blog post:
https://www.baader-planetarium.com/en/blog/preshift-and-further-information-concerning-baader-cmos-filters/