Description Hook’em Double Copper Sleeve Crimps Product Specification Table: Size Quantity Per Pack 1.0mm 20 1.5mm 20 2.0mm 20 2.5mm 20 3.0mm 20 Hook’em double copper crimps or ferrules are designed to work with a specific-sized cable to get the maximum benefit and breaking strain of your rig. For the most effective connections, a hydraulic tool is suggested. Manual mechanical connections will not be as effective or strong. Hook’em double copper crimps are available in 5 size options.