The stainless steel Wichard Shackle is common tree climbing hardware typically used on the tail of 'home-made' rope savers for retrieval. Prior to the arrival of the Treemagineers pulleySAVER, the Wichard Shackle was used extensively on home-made rope savers utilizing the ART Cocoon and ART Link pulleys.
Once the DMM Pinto Rig became available, tree climbers swapped out their ART pulleys for the newer DMM option.
Friction from the rope drags the Wichard Shackle towards the Pinto Rig during the climb, particularly in descent. As it happens, the 'snap' on the Wichard gate locks perfectly between the becket and the sheave on the DMM Pinto Rig, jamming it into place, and in the process, gouging rings into the aluminum sheave on the Pinto (see picture below).
The Treemagineers PulleySAVER has a stiff 'leg' above the retrieval snap which presumably gets around the problem (of the snap riding up into the pulley).
But… there's a positive upside for the Treemagineers. Climbers with 'home-made' rope savers are now opting for the genuine article (pulleySAVER), retiring their newly purchased, superficially damaged Pinto Rigs to other climbing and rigging applications.
Thanks to Auckland contract climber, Freddie Hjelms for the above Pinto Rig images. Freddie's Pinto Rig was damaged during his week with the NZ Department of Conservation in the beech forests of Deep Cove, Fjordland. The trip was organized by Jerry Lynch.