Holy crap! 1,800$?! C'mon!

Otherwise a brilliant idea. So I guess it works like one of those dog-leash dispensers, with car seat-belt breaking mechanism? Interesting idea, though I'd be really worried so many mechanical parts....

The Redpoint descender units are pretty well engineered and well made. They have a very well established service history in climbing gyms around the world.

If you can develop, engineer, manufacture, and distribute a better and/or cheaper auto belay unit, you should do so.

Thanks, Bob "BoKu" K.

I did some research and found they had a recall a while ago... so it's not without a potential for failure.

Sorry to be stupid but what do you mean by putting some weight at the bottom?

Recalls are often a sign that things are as they should be. A defect was found, and a process was developed to ameliorate it.

One can argue that the set of man made things without potential for failure is empty.

Thanks, Bob K.

I solo top rope all the time using a Petzl shunt which has not failed me yet even after some big wipe outs

RA_Testing_Paper Pages 5&6


Petzl Shunt

The Petzl Shunt is the most common rope
access back-up device in use world-wide.
The device is a “mechanical-prussik”
originally designed to back up rappel
devices for recreational users. It can also
be classified as an ascender. While the use
of the Shunt in the industrial environment
has been controversial from the beginning,
and is clearly outside of its original design
parameters, the 2001 Lyon Equipment
report raised serious concerns about the Shunt’s ability to adequately withstand the
forces subjected to it during a fall. The Lyon
testing showed that slippage distances were
excessive and the Shunt was prone to
detaching from the rope if a knot was encountered before the device came to a stop.
The data from the Lyon Report led us to expect poor results from the Shunt,
however our testing showed otherwise. In our tests, the Shunt proved to be one of
our most consistent performers on the 11mm ropes (measured diameter) yielding
low impact forces and reasonable slippage distances.
The Shunt performed poorly on the Beal 10.5mm (10.1 measured diameter),
confirming the results of the Lyon Testing. In all three cases the device slipped in
excess of 3 meters before hitting the knot. In order to give the Shunt every
opportunity to perform on the Beal rope, we tested it in a factor 1 fall using a 1
meter dynamic rope lanyard (cow’s tail), replicating the most realistic one-person
field configuration. Again, the Shunt performed poorly, allowing the test weight to
drop nearly 3.5 meters. It hit the knot on the first drop at 2.3 meters. This led us to
conclude that the Shunt should NOT be used as a back-up when paired with ropes of
similar diameter to the Beal 10.5 mm.
The 200kg, factor 1 tests showed some of the Shunt’s limitations. We didn’t bother
testing the Shunt on the Beal rope with the 2-person load. The Shunt hit the knot
and detached from the rope on one of one drops on the thinner Blue Water rope and
one of two drops on the PMI 11 mm. The Shunt performed remarkably well on the
thicker Sterling HTP (11.6 measured diameter). The reasonable conclusion is that
the Shunt performs better on ropes of larger diameter.
The Shunt will not conform to the requirements of the U.S. fall protection standards
because of it has a relatively weak body, it can be defeated by the user, and it does
not self-trail. However, at this point the Shunt should still provide a safe option for a
rope access technician provided it is paired with the correct rope diameter and
proper operator training.


© Ropeworks, Inc and U.S. Bureau of Reclamation 6
Report available in electronic format at http://www.ropeworks.us

Thank you for that, it is easy to take things for granted and my rope is a Beal 10.50, I will look around for another thingy to arrest a free solo rappel