Adjustable mast chock - with 6 sheaves - 205 mm stroke

Sprenger asjustable mast chock, due to the 6-fold traction force, halyards or stretchers of the sails can be optimally trimmed even under load with the help of the stretcher. Seawater resistant aluminum, black anodized, with rope, Made in Germany. The stretcher is also widely referred to as a beer crate or magic box.