Petzl Shunt

Summary

Unnecessary, "psychological" backup.

I was terrified of rappelling and ascending ropes 14 years ago. So I bought the Shunt as a "back up" in case I messed up a rappel.

The Shunt connects from your harness to the rope above your rappel device. To descend, you must use your non-dominate hand to hold open the cam. If you let go, the cam slams shut, pinching the rope and halting your descent.

To that end, this device works fine.

HOWEVER, human nature in a fall is to grab hold and squeeze tighter. In a panic situation, a person does not unconsciously let go (next time you're with a driver who slams on the brakes, notice your clenched fists afterwards). So in order for the Shunt to actually work, you have to intentionally let go at a moment when your nature reaction is to squeeze tighter.

The Shunt gave me the initial psychological security I needed to get use to rope work. But once I became familiar and accustomed to my equipment, I realized how useless this piece of equipment really is.

Save your money and take a quality rappelling class!