Male thread threads into eisting M18 1.5 O2 plugs, bolton, no cutting or modification of stock wiring like an electronic CEL FI MIL Eliminator.Installation This oygen sensor restrictor should NOT be installed with the primary oygen sensor sensor before catalytic converter, quick and easy installation with no modifications required.Application This oygen sensor restrictor CEL Fi Fouler with adjustable gas flow inserts. Check Engine Light,For offroad racingtrack use only, prevent the CEL CHECK ENGINE LIGHT MIL MALFUNCTION INDICATOR LAMP from lighting up when removing the original catalytic converter.When installing a high flow catalytic converter on your car or truck, your Check Engine Light CEL may light up due to increased air flow. An oygen sensor spacer places the rear oygen sensor out of the path of the ehaust. An etension spacer only minimizes the risk of CEL. Some vehicles require their ECU to be reset if the CEL is triggered prematurely. This product will work on your specific application. This kit allows for a correct and customizable installation position. Our oygen sensor etension kit is machine TIG welded for an eact fit. The threads are precision cut for a proper seal to prevent ehaust leakage and maintain accurate sensor readings. High quality condition. Fits all M181.5 threaded oygen sensors. Durable corrosion resistant plating,. Fits all vehicles and ehaust systems with M18 1.5 oygen sensor holes. For use with the vehicles spark plug spacer to eliminate the check engine light. Easy installation Straight bolton, no modification required. Very easy to install. Color Silver Material Iron Size 2232mm Package Contents 4 Oygen Sensor Thread Only the above package content, other products are not included. Note Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 13 cm.