This butt box is compatible with Gamakatsu's grouper rods (Grand Impulse, Gamakue Impulse, Dora). Manufacturer: FMW Material: Super duralumin ■About the Material Made of super duralumin, a lightweight, high-strength material also used in aircraft. The specific gravity is only 2.8g/cm3, less than half that of stainless steel (7.93g/cm3), making it lightweight. Furthermore, the tensile strength is approximately 570N/mm2 for super duralumin, compared to approximately 520N/mm2 for stainless steel, boasting high strength. Each piece is produced by cutting from the material, so the cost is inevitably high, but the absence of welding points reduces the risk of breakage. → #Other FMW products are here 【Sea bream, Longtooth grouper, Grouper fishing, Bottom fishing, Piton, Ishizuki BOX, Rod holder】