EFI has been the leader in developing the standards for the transient voltage suppression technology. These standards now have become the model for the industry. The development of the hybrid multi-stage transient voltage suppression technology by EFI has revolutionized the and optimized the protection by combining the basic suppression components. EFI’s sinewave tracker circuitry has been copied by most every one establishes power surge clamping window relative to power sine wave voltage in contrast to fixed voltage. Furthermore, EFI’s  multiple diagnostics which alert the facilities personnel of the power problems and thermal fusing that eliminates over heating has become industry standards. In the past 30 years EFI has lead the industry standards  to improve product reliability and effectiveness. Please let us be part of your electrical protection scheme. All of our TVSS products are built to the National Electrical Code and UL 1449.