Focomat Ic and Valoy II negative holders with glass?

I printed with Focomat Ic and Valoy II enlargers for many years and always used their glassless negative holders. Between my Leitz parts was a 4x4 holder with glass and recently this holder solved a problem. Then I found the same holder but for 3x4. Attached a picture of these negative holders.

I don't find these holders in the Leitz Focomat or Valoy manuals, at least they don't speak about glass.

Does anyone have different information? And does anyone know if this negative holder with glass was also made for 24x36 ?

Thanks ! Michael