The NECK TENSION GAGE TOOL by FORSTER PRODUCTS, INC. is designed to measure and create consistent neck tensions for .243 caliber reloaded rounds.
This tool is used after case neck sizing and before bullet seating to check for optimal inside neck diameter and the presence of "donuts" at the neck-shoulder junction.
It includes four stepped diameters for measuring, with each size etched on the tool, and the kit comes with all 5 calibers for versatility.