Mystery part of LPL C6700 enlarger?

I recently acquired a second-hand LPL C6700 enlarger. In the box it came with, I found this filter-like thing (see image, and sorry for the embarrassingly poor quality, I was in a hurry and just had my phone at hand...). Does anybody know whether this is part of the enlarger (and if so, where does it belong)? Alternatively, what is this and what can it be used for?

Incidentally, when testing the enlarger, I found it to have very short exposure times (only 1-2 seconds even with the lens fully stopped down), but this is more likely because I tried to do small prints (3.5 x 5 and 5 x 7 inch) from 6x6 cm negatives with a 75mm lens (I will have to try again with a longer lens to see whether things work better then). So, it probably does not have anything to do with that part? (Also, if anybody has any better hints on making small prints from 6x6 cm negatives, I'm very glad to hear them. I was thinking whether there was such a thing as ND filters for enlarger lenses, but I can't quite figure out the filter threads of the various lenses. Are there maybe solutions that go behind the lens rather than in front of it as this all would be standard 39mm screw mount?)

It seems a diffusor for integrated light metering.

It would be mounted at a rod next to the lens and swivel, as those red filters.

I'm pretty sure I posted a PDF of the manual here at some point, but I can dig it out of my file if you can't find it. Let me know.

@AgX: Thanks for your information. I received further information in a private message and it seems that it actually does not belong to the LPL enlarger but is a diffuser for a color analyzer, so you're right about where it belongs.

@ParkerSmithPhoto: Thanks, I know of this version of the manual here http://www.jollinger.com/photo/cam-coll/manuals/enlargers/lpl/LPL%20C6700.PDF However, it is not very detailled (in particular w.r.t. the insides of the enlarger), so I was wondering whether that filter thing belongs somewhere inside the enlarger, but this does not seem to be the case, see above.

Using a longer lens, if the bellows are long enough, will give you more space between lens and baseboard but it won't change the exposure time more than the innacuracy between marked apertures on the lens. You are still squirting the same amount of light, through the same neg, on to the same area of paper.

If the head is a condenser based one, using a single PH-style (ie. normal shape but better quality filament position and white coating), then replace it with a lower wattage bulb - for example 75W instead of 150W. Also possible would be neutral density in the filter drawer, even a piece of white writing paper would work as a temporary filter, or a couple of offcuts of diffusion scrim.

If the head is a modern-ish colour head there should/could be a negative-density wheel in addition to CMY, possibly marked 'K' or 'D'. This was indeed because people often make small colour prints and RA4 paper is generally faster than black-and-white paper, which makes the short exposure-time problem more tricky.