Yann: I reproduced your test at home using (1) a brand new Shunt and (2) a 9.5mm dynamic rope. It failed in exactly the same way as you demonstrate, if the device gets flipped upside down. I bounced about 2cm up and down, 3-4 times, to get the rope to release. I am about 72kg.

I am the third climber... Accident in august. 2 meters' free fall using shunt. Had no backup at that time because still didnt land on petzl webpage, i wasnt prepared enough... 15 days of absence from work. almost broken ankle in "Vecchiano" crag. one month with crutches. Italians stole all my equipment I had to left in the crag. I was doing a traverse movement when Shunt just... disengaged. I saw the shunt just disengaging when rope wasin a traverse configuration. Now i would restart, i am deciding what equipment...

Good demo - it's surprising that the device is stable like this and not self resetting. Obviously, it needs a test with a new device but having seen how thin ropes can stretch under load and the geometry of the device which would allow flex, it isn't totally surprising that this can happen.

Thanks, I heard before, that the shunt can fail. Nice to see it finally to happen. Right from the start I always used a backup which can’t fail and a main device without teeth

Good PSA. Saw it on BetaClimber fails.

Very timely. I've just received a Shunt but have not tested it out yet. Thank you.

Very interesting, thank you!

Wow. I think you just saved my life. I had been looking at a shunt as a cheaper option than a Gri Gri, since I'm on a tight budget. I think I'll wait and save up more money for the gri gri. Can't thank you enough.

Petzl is not clear enough about it: telling that "the SHUNT is not recommended for self-belaying because of the risk of the cam jamming in an overhang situation" implies that it would be recommended in other situations... This is a dangerous statement.

that is insane! Thanks for sharing!

good to know, but I will keep using my shunt WITH a back up. it's a very handy tool in my opinion, and i like how i can also use it as a prussik when I rappel. But, I definitely see your point, but like i said, if you have a solid back up that shouldn't be a problem.

Wow, thank you! Im just getting into TRS and people need to know this! Subscibed!

If the top rope is weighted, say, with a climbing pack with 20lbs of rocks in it, is it still possible to get the device to invert? Seems like this failure mode is only possible if the line is slack pr perhaps in a very weird fall scenario.