We blogged about the popularity of our DMM product range on the weekend and included a picture of new products from the 2010 DMM Professional Catalog. This picture has generated a bit of debate, both on the website and with climbers visiting the Treetools store.
A discussion thread relating to this picture featured a couple of weeks ago on ArbTalk. Below is a different angle of the same rigging set-up and here is the Treemagineers explanation by Chris Cowell on ArbTalk:
"You are looking at a lowerable basal anchor for a SRT ascent line!
There is an adjustable sling around the bottom of the pine. The white/green rope has a Prusik loop on it (the black/green cord) which is girth hitched into one of the slots of the small Hub. Once the ascent line is set, a bite of rope is passed through the inner of the Hub and a karabiner is passed through the bite. The tail of the ascent line can then be tied off (e.g. two half hitches) and the Prusik is blocked so that it can not slip.
Should it be necessary to lower the climber during ascent, the small green Prusik acts as a backup to the friction device which has been created by the ascent line passing through the Hub and over the karabiner.
This application demonstrates three generic attachment options for Hubs:
1) stationary textile (e.g. the girth hitched Prusik cord);
2) running textile (e.g. the ascent line through the inner ring); and
3) connectors (e.g. the single oval karabiner)
There is a bit more info about Hubs on the manufacturer's website .
We hope that Chris's explanation helps solve the problem.