PETZL MAESTRO® S**Special Order Item: 2 4wk lead time** Descender with integrated progress capture pulley for loads up to 250 kg, compatible with 10. 5 to 11. 5 mm ropes MAESTRO S is a descender designed for technical rescue operations. It facilitates manipulation of heavy loads, for lowering or hauling, and may be used in both the primary system or in a back up belay. This versatility allows rescuers to adapt to any situation they may encounter on the rescue scene.