What Code is Maerklin Z gauge rail?

[Meiriongwril]

I've checked websites, but cannot find what code Maerklin Z gauge rail is.

I'm thinking of using the Aspen mixed N/Nn3 rail, and would like to know which rail height option to go for.

 

[Triplex]

I think it's Code 55 - hugely oversize. Even Code 40 in Z would be the same scale size as Code 55 in N or Code 100 in HO.