BAB series foil strain gages are produced from Karma alloy on a fiberglass-reinforced polyimide backing. In comparison with conventional Constantan alloy, Karma alloy has almost linear thermal output in -20…+250°C temperature range. Special backing provides excellent isolating qualities at -269…+250°C long-term and up to +350°C for short-term. These strain gages are supplied fully covered with a protective polyimide film, and with high-temperature lead wires.