{HEAD ~ The palladium} based {TAIL ~ three way catalyst} may be palladium or palladium with another noble metal like rhodium 
based
{ HEAD ~ The palladium } based { TAIL ~ three way catalyst } may be palladium or palladium with another noble metal like rhodium
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH