For fast changeover of un-winder/winder rolls Air Expanding Shaft is required for core holding. Through its air valve air can fill and the air shaft will hold the core firmly by expanding the rubber bladder. Core gets released after removing the Air by thump press. Most commonly used cores are 3 ID core but bigger cores are also used where heavy weight of the unwind/re-wind rolls. Air Expanding Reel Shaft is core-holding device suitable for 3 core inside diameter & 70mm core diameter.