Protecting your bulb from accidental spray & keeping the enclosure clean are two primary functions of a lens. Another important benefit is that the lens will act as a heat barrier, allowing beneficial light through and redirecting heat back up & out of the top of the reflector. Helps prevent bulb rupture due to moisture contact. Required for adapting the Sunburst, Radiant, Daystar 4 & ValueBrite series into Air Cooled Canopies. Lens included with Daystar 6 AC, Radiant 8 AC & Growzilla reflectors.