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C.A.M.P. Big Wall & Protection Dryad Small Double Pulley 2156. It features a large primary attachment hole that accommodates two carabiners and a lower becket hole for a single carabiner. Self-lubricated brass bushings are perfect for light applications at low speed. Prusik knots can be installed on either side (aramid cord suggested) making it particularly useful for crevasse rescue scenarios.
The Camp USA Dryad Double Pulley is for creating haul systems. Fits ropes up to 13mm for a wide range of use and also allows for 2 carabiners. Features of the Camp USA Dryad Double Pulley Compact double pulley Self-lubricated brass bushings Aluminum alloy body and sheaves Stainless steel axle Prusik-minding