- Sheet: Higher numbers mean thinner material. Armour in period would vary between 22 gauge, up to at least 10 gauge or more, depending on the application. Modern armour is commonly found in 16 gauge for limb defenses, and 14 to 12 for helmets.
- Wire: Gauge defines the wire diameter. As with sheet steel, a higher number means thinner wire. Maille armourers must commonly deal with gauge. Common gauges are 16 and 18.
It is important to note that material manufacturers allow a degree of variance in their products. Therefore, a sheet of steel listed as, for example, 16 gauge may be slightly thicker or thinner. Determining gauge is commonly done with a caliper.