This O2 cel fix actually has a miniature catalytic converter inside and will help annoying check engine light you get after modifying your exhaust or removing your catalytic converter,and sometimes even when installing a high catalytic converter.'t take a chance on using an extension only as often they do not work,this is a real mini Catalytic Converter into it.This O2 cel fix with miniature will trick your ECU into thinking the stock catalytic converter is still installed.When you remove your catalytic converter,your post O2 sensor will see higher temperatures and greater of unburnt .Weight:90GThread: X 1.5Color:silvermaterial:metal Package Contents:1* oxygen sensorOnly 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 +/- 1-3cm.