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Progress Adjust Zyper


Progress Adjust

Front Rear
Front Rear

Technical Details

I acquired my Petzl Progress Adjust from Inner Mountain Outfitters at the 2017 NSS Convention.

The metal portion of my Petzl Progress Adjust is 21 mm. long, 70 mm. wide, 40 mm. high, and weighs 181 g. The lanyard is made from 11.5 mm. dynamic rope. One end has a sewn eye for attachment to the harness. A rubber grommet is provided. The other end of the lanyard is doubled back on itself, sewn, and covered with a plastic cover held in place by a plastic sex bolt. In other words, there is no eye at this end. The lanyard is 1 m. long.

the front is printed with the Petzl logo, an arrow, and a scanner code. The rear is stamped with "PAT." and an arrow.


The Progress Adjust is a nice adjustable lanyard that seems to work well. The lanyard is large enough to handle the shock loads that can occur if one slips near a rebelay.

Some cavers prefer prusik-based adjustable cows tails, and others, like me, prefer fixed length cows tails for general use. The tradeoffs involve complexity vs. simplicity. Minor weight savings are another consideration.

There is a double version that has a fixed-length end for attaching to an ascender. I do not have this version. If the fixed-length end is exactly the right length for your height and arm length, you might want to look at it; otherwise, you may wish to choose an option with the proper length for your body.

Instructions Instructions Instructions Instructions



Technical Details

I acquired my Petzl Zyper from Inner Mountain Outfitters in 1997.

My Petzl Zyper is 40 mm. long, 109 mm. wide, 14 mm. thick, and weighs 294 g. The brake is a piece of forged aluminum with one round and one elongated "teardrop" shaped hole. The 13 mm. cord has a loop sewn at each end and covered with plastic to protect the stitching. The distance between the two loops is about 170 cm.

One side of the brake is stamped with "ZYPER," "PATENTED," and "PETZL." The other side is stamped with "ZYPER," "CE0197," and "PETZL."


Via FerrataThe Petzl Zyper is designed as a dynamic cow’s tail for use on via ferrata.

The newer Zypers came with a sewn webbing loop for attaching to the seat maillon. Mine is an older model that does not have this feature; however, I can use a sewn spectra sling to accomplish the same goal.