The advanced multi-surface reflectors (MSR) with crystal clear glass lenses produce a 45% more luminous beam on low beam and 30% more luminous beam on high beam than conventional "Throw away" head lights. The durable diecast aluminum reflectors utilize separate and replaceable H4 Halogen street legal 55/60 watt bulbs that are SAE/DOT approved. Simple direct plug and go installation. No modifications required. Sold in pairs.