My brothers and I are going through things in my Mom's house now that she has passed and they don't seem to be bitten by the Maerklin bug like I was.
As I built my own collection, I bought my own M, K and C Track and never used the track that we first played with as a child.
I am thinking that the track with solid centre rail may be of more use to somebody who has a collection of that kind of track.
In addition to a number of track pieces (straight, curved and switch tracks), the collection also includes pieces like the bridge section and others.

If you are using M Track with solid third rail and may be interested in finding more out about what I may be able to offer, please contact me by private message.

Regards

Mike C