CLB-Series Thermal Circuit Breakers Carling Technologies CLB-Series Circuit Breakers are compact, single pole, pushbutton thermal circuit protectors. This series is highly reliable and highly resistant to shock and vibration. With few moving parts, the cost-effective Carling CLB-Series Thermal Circuit Breakers are designed for use in household and commercial appliances, transportation, marine, telecommunications, power strips, audio-visual, medical, and power supplies.