Are you deleting the EGR on your Miata or installing a 1.8 in your 1.6 car? Then you need this to plug the fitting on your header or exhaust manifold. Fits 1999-00 EGR fittings. Also fits our 1.8 turbo manifolds and the 2004-05 Mazdaspeed stock part. Please note that using this part on a car fitted with a 1994-05 stock computer will result in a check engine light.
For 1994-97 and 2001-05 fittings, we have an EGR cap.
These year ranges refer to North American vehicles. EGR designs varied in other countries. Please confirm if your manifold has a female fitting (which uses this plug) or a male fitting (which requires our EGR cap instead). It's our understanding that most European cars use male fittings but it's up to you to check.