This little ascender from Petzl is a favorite of arborists for tending slack with a rope lanyard.

Climbing instructor Genevieve Summers uses the Microcender as a rope grab in conjunction with a set of stirrups, to assist in Doubled Rope Technique climbing. It is easier to lift than a prussik and she likes that it also doubles as a slack tender. It advances up the rope easily and the cam releases with a bit of pressure from your thumb to lengthen and slack your lanyard.

Intended for moving on fixed ropes (as a back-up belay), for hauling heavy loads, and as a progress capture device in hauling systems. Not for fall-protection use.

• Very compact and lightweight.
• Slides easily up the rope and jams when pulled down by the cam.
• Slides easily downwards when pulled down if the cam is held in.
• If overloaded or subjected to an impact force, the rope may slip through the device.
• Locking pin gives greater safety: separation from the rope requires two separate actions.
• For use with single ropes 9mm to 13mm (3/8" to 1/2") diameter.