Flame-Thrower digital rev limiters work with any 4, 6 or 8 cylinder engine using points, OEM electronic (GM HEI, Ford, Chrysler) or aftermarket inductive type ignition systems including our very popular Ignitor and Ignitor II points replacement systems. This digital microcontroller based unit provides a much greater accuracy (+/-0. 01%) over analog systems. There is no need for old resistor style pills or chips, our easy to use rotary switches adjust the RPM limit to an ultra fine resolution of 100 RPMs. Random spark stealing method provides superior control of rev limits and a rapid response time to over rev limit events, preventing engine failure. Once the established RPM limit is reached, random spark stealing starts within one spark, reducing plug fouling common with repetitive stealing type limiters. Rev limiters come with multiple analog filters and one digital filter to prevent coil noise interference from affecting the established rev limit. Installation is a snap with a four wire hookup and easy to understand instructions. The rev limiter's small size permits installation in even the most crowded engine compartment. Features: Digital microcontroller based unit provides greater accuracy (+/-0. 01%) over analog systems. Easy to use rotary switches permit settings with a resolution of 100 RPMs. Random spark stealing method. Tachometer output with TTL interface and near 50% duty cycle make our limiters compatible with most modern tachometers. Reverse voltage protection. Easy four wire hookup. Compact size: 3L X 2. 5W X 1. 4H Light weight: 0. 75 LBS. Limited One Year WarrantyPit Stop USA offers PerTronix Digital Rev Limiter 600 at low everyday prices. Be sure to check out all of our products from PerTronix Performance Products including PerTronix Performance Products Rev Controls.