With SHIMANO's DIAFLASH construction, the outermost layer of the butt section is diagonally wrapped in opposite directions with carbon tape, which forms an array of "X" shapes. The width of the tape, its winding angle and the part of the rod being wrapped are fine-tuned according to the rods intended use. DIAFLASH is a reinforced structure that prevents twisting of the butt section in situations where high-intensity pressure is applied.

When an angler assembles the different rod section of the telescopic rod, according to the SAS indication marks, a better, more constant action is achieved.