In reply to chers:
> (In reply to fred99) Not sure I quite understand your set up there, or what the advantages are? So you are only secured by 1 screwgate when lowering, is that right? Seems just as easy to me to use 2 quickdraws and clip into both tolower off.
No, secured by two screwgates.
If two ropes used, put one through each screwgate (prevents ropes rubbing against each other).
If one rope either put it through both screwgates, or just through one if you like. Whichever option, the two scregates are attached to each other by the (shortened to reduceshock-loading to a minimum) sling.
The main advantage versus using quickdraws (or any form of open gate carabiner), is that if you use this for top-roping there is no worry about ropes coming out of the gate when tension is removed. You are effectively duplicating the set-up at an indoor wall.