Mathieu says he bolted the route last winter. It starts in a cave on the right part of the crag and is severely overhanging all the way and exits through a dihedral. He says it's more difficult than all the 9a's at La Balme and that he suggests 9a+.

Speaking of 9a's and up, La Balme now has eight of those, meaning it's the French crag with the most hard routes, More than Céüse!

Source: Kairn