Unique underpass refractor: Redirects light from drivers line of sight and spreads light across multiple lanes of traffic. More efficient precision reflector: Provides up to 55% higher street side output than competitive units. Adjustable optics: 50° or 60° main beam optimizes one or two sided designs and visibility. Borosilicate prismatic glass refractor: Non-yellowing, precise control with minimum glare. Corrosion protection Low copper aluminum housing, phosphate pretreatment and 2-4 mil polyester powder finish provides long life where salt and alkali leachate is a problem. Protected HPS starter: Shuts off when lamp fails. Prevents starter failure and ballast thermal damage from continuous operation. Multiple wiring access: Wallpacks can be wired from side or back. Wallpack® III features optional thru wiring capability.