Ringed cambium savers from Stein or more recently Teufelberger have long been standard kit for arborists. Rope savers which incorporate a pulley like ART and DB Tree are considered top end (or for very experienced climbers only).
Now Edelrid has introduced the Roka-e - a 'ring' style cambium saver with integrated pulley wheels (like the DMM Revolver) to reduce friction. The Roka-e should offer excellent price/performance over the pulley models and provide stiff competition for the basic ringed versions.The custom designed 'pulley rings' are attached to a new 3-layer 16 mm tape. The Roka-e comes in three fixed lengths: 90 cm, 120 cm and 150 cm. All parts are replaceable so worn equipment can easily be replaced - and climbers are bound to find other uses for the 'ring' pulleys.
The Edelrid Roka-e should be available from Treetools mid 2010.