This is a general term used to describe the combined use of two tackles in which the moving block on one is clapped on to the hauling part of the other; its mechanical advantage is the product of the mechanical advantage of each tackle.
Eli ligama elisoloko lisetyenziswa kudityaniso lomsebenzi wentambo zenqanawa ezimbini apho ujikelezo lovingco kwisinye luqhubeka ekutsalweni kwendawo kwelinye icala uncedo lomatshini lusisivuno soncedo lomatshini lwentambo kwinqanawa nganye.