Supertech valve protection. Newly redesigned and now fully CNC machined for a higher quality and finer finish. Fits: BMW M20 B25 2.5L 12v / E30 / E34 325/525 '77 -'92 References: Triple grooveSupertech valve locks.Newly redesigned and now fully machined on CNC for higher quality and more accurate finish.Fits: BMW M20 B25 2.5L 12v / E30 / E34 325/525 '77 -'92References: triple groove