Holstein's Knock Sensor Kit for select GM and Isuzu vehicles is a great solution for replacement of the entire knock sensor system - both sensors and the harness - all in one box. Holstein knock sensors are direct OE replacements for these critical engine components, offering perfect fit, form and function for flawless operation that protects your engine from damaging detonation and pinging in all types of driving conditions. Precision engineered sensor exactly duplicates the function of the OE component, providing critical information to the vehicle's ECU so it can adjust engine timing to prevent internal engine damage when detonation occurs. Manufactured with premium materials that ensure rugged, long-term performance and the heat resistance necessary to withstand high engine operating temperatures. Exact OE connectors and attachment points ensure a trouble-free installation process. Fully tested to ensure voltage matches OE specifications. Kit includes two (2) knock sensors and one (1) knock sensor harness. Backed by Holstein's 3 year/36k mile warranty - we believe in our parts and our warranty shows it! Arrives packaged in a Zip-Loc style anti-static bag that protects the electronic circuitry and components.