Once again, thanks.

in the translation:

"Only planes built from factory kits or in
series production may be used for towing, if declared approved by the
factory and the approval statement printed in the certificate of the
aircraft".

I am somewhat unclear about whether it applies to the preceding sentence(ultralight gliders) or in general.

The Virus SW 100, for example, is certified for heavy tows by the manufacturer, the LBA and is in series production, could that be used to tow "normal" gliders?

Vassilios

at 3Euro/lt for 100LL,
you can understand the motivation