M18X1.5 Male To M10X1.25 Female Coupling Reducer Adapter Stainless Fitting Male Thread: M18X1.5 Female Thread: M10X1.25 Material: Stainless Steel Washer included Coverts standard M18X1.5 02 sensor thread to M10X1.25. Commonly used on Nissan SR20DET Fast and free shipping from USA!