Memory safe function stores settings eliminating unintended changes to Rev limit. Adaptive dwell maintains peak energy throughout the entire RPM range, reducing misfires while improving engine performance.Peak current level is reached just prior to spark for maximum energy without the heat build-up, increasing coil performance and module reliability. Adjusts spark timing at higher RPMs to compensate for inherent electronic delay. Senses startup and increases energy for quicker, easier starting. Thermal clad surface mount construction for superior reliability. Built-in reverse polarity and over current protection shuts down the system, preventing component damage. Not compatible with CD or Multi-Spark boxes. Legal in all 50 states and Canada. The item "Pertronix 71181 Ignitor 3 III Multiple Spark Ignition Module GM 1957-1974 V8" is in sale since Wednesday, November 15, 2017. This item is in the category "eBay Motors\Parts & Accessories\Car & Truck Parts\Ignition Systems\Electronic Ignition". The seller is "horsepowerclub" and is located in Fort Lauderdale, Florida. This item can be shipped worldwide.