The Lock-N-Load Headspace Comparator extends brass life, improves accuracy, and enhances safety. The gauge measures variations in brass before and after firing or re-sizing. It allows for headspace comparison between fire-formed brass and re-sized brass. The included bushings provide the ability to check most bottleneck cases from .17 Rem through belted magnums.

Features:Measures variations in your brrass before and after firing or re-sizing;Allows for comparison between fire-formed brass from the gun and re-sized brass;Bushing sizes: .330", .350", .375", .400", .420". Most bottleneck cases from .17 Rem through belted magnums