GA-4-A The Cable Diameter Gauge is the perfect tool for measuring cable. This aluminum wire gauge has a silk screen finish, making it easy to read. It measures from 1/16 in to 3/8 in., with both inch and metric measurements. The minimum measurement is 1/16 in., while the maximum is 3/8 in. The Cable Diameter Gauge will allow you to accurately measure cables of any size, saving you time and money.