Elna serger, model 925 DCX. Clean and nice, in great condition, gently used

Description

Elna serger, model 925 DCX. Clean and nice, in great condition. I don't know how old this machine is, but according to Elna's website, this model number was first produced in 1996 and was the "first domestic overlock to offer three variations of the cover hem, including triple cover hem."
It comes with four feet, a box of tools, extra cones of thread, two instruction books, the necessary foot controller & electrical cord, plus a dust cover.  I haven't operated this machine; I acquired it two years ago (Dec. 2019) from a neighbor whose wife had just died. She was an extremely nice person, but finicky! She always took scrupulous care of her belongings.
I had intended to learn how to use the serger myself, but always put it off (OK, I was a bit intimidated). Besides, I use French seams and flat-felled seams for finishing, anyway, and I don't sew knits, so this seemed like more than I really need. After feeling guilty for owning it for 2 years without tackling the instruction books, I'm passing it on.
The machine has hardly any dings, stains, or flaws. The dust cover has a couple of minor spots. And one of the attachments (see last photo) has some gray streaks where I think she marked lines for some purpose or other. I have no idea what this attachment is for, or whether it in fact belongs to this machine. I also can't tell you whether all the original pieces are here, but see the photos for what's included. I recommend taking it to an Elna dealer for oiling--I haven't had it serviced since I've owned it.
The machine will be carefully packed, in a box within a box, and padded by slabs of egg-crate foam.