The Loos economy tension gauge takes the guesswork out of cable tension adjustment. It's especially designed for accurate, repeatable tuning of a sailboat's standing rigging. Manufactured of rugged anodized aluminum, the gauge is corrosion -resistant and will provide years of service. Please read the detailed operation instructions that accompany the gauges carefully to ensure complete accuracy. Cable sizes: 3/16", 7/32", 1/4" and 9/32"