The Unicender is an ascending tool that is specifically designed for arborists. It is made of milled 6061-T6 aluminum. The device vaguely resembles a bicycle chain link with specialized teeth and gears standing on the chains.
This unique device can be used in both the double and single rope techniques both as an ascender and descender. This makes it far safer than using separate ascender and descender devices by eliminating any dangerous change of tools while at the top of the climb. Beginners as well as professionals would definitely appreciate this feature.
In a double rope, it is used as a mechanical split tail taking the place of a friction hitch. For single rope techniques, it used both as an ascender and a descender. The rope is snaked through the specialized gears which apply friction to the climbing line. When descending, a climber simply squeezes the gears. There are two possible configurations for a descent. The Unicender can be arranged in a way that squeezing it allows descent, like a friction hitch; or squeezing means stopping a descent, like a figure 8.
There is only one size for the Unicender but it can accommodate ropes sized 7/16 and ½ inch.