Since 1937, CITEL Inc. has manufactured a complete line of Surge Protective Devices (SPD) to protect sensitive equipment from the harmful effects of lightning strikes and other power line disturbances. CITEL is a world leader in Transient Voltage Surge Suppression products and components including AC power surge protection, DC power surge protectors, RF coaxial surge suppressors, and the component Gas Discharge Tube (GDT) surge arrestor.