Surge Arrestors also known as Gas Discharge Tubes or Surge Voltage Protectors (SVPs), are hermetically sealed ceramic tubes consisting of two or three electrodes (one or two chambers) spaced by insulators and filled with a rare gas. EPCOS brand GDTs cover a wide spectrum of protection and switching applications - from light to maximum duty, from standard devices to customized products. EPCOS is able to find the best match for the most diverse requirements.