This should be the hardest via Ferrata trail on Triglav Mountain, the highest mountain in the Julian Alps and Slovenia: 2864m.
It is signed ad B/C but is mostly A/B, so the via Ferrata kit is recommended but -in my opinion- not mandatory. If you're planning to do this hike in June you might encounter a lot of snow on your path, better have some spikes.
The path (especially at the beginning in the forest and on the topo if there is snow) is not really well signed: GPS track and power-bank should be taken.
Some scrambling experience (2-) and not being afraid of highs are needed.
There is the possibility to split this hike in two days and sleep in the Triglavski dom.