New and improved, these fly-fishing Airlock Indicators are made of a lighter weight material for easier casting and higher floatation. Biodegradable EVA foam tracks straighter than conventional plastic. Improved durability with no more dents, leaks, holes, or cracks. Remove the nut and place your leader in the notch in the threaded stud that is attached to the indicator. Then simply replace the nut and twist to tighten. 3 indicators per pack in assorted colors.