A sealed beam lamp is a headlight which is housed in a sealed unit containing the lens, reflector and the element. Prior to the introduction of the sealed beam the headlamps were constructed of separate parts. This caused out of aim headlights that were easily burned out due to moisture entering the light assembly. This also led to failure in very inclement weather.
The benefits of a sealed beam headlight include ease of maintenance as well as improved functioning characteristics. With the head lamp being sealed, thinner and clearer glass could be used to build the lights. The lack of contaminates entering the light aided in brighter reflector material. This all added up to a better and brighter head lamp, which allowed a vehicle operator to see much further ahead of the vehicle. It also allowed the sealed beam to illuminate the night roadways much more clearly than had ever been accomplished with a traditional headlight.
Sealed Beams are becoming increasingly difficult to obtain. Many classic and antique automobiles have undergone a seal beam transplant or conversion. This type of seal beam conversion is in the form of a bulb holder in the rear of the lens. This offers the utmost in original equipment appearance combined with modern safety components.