These 3-1/4" round lenses were used in the 1960s and 1970s on BeeLine, Coastliner, Garway, Layton, Mobile Scout, Nashua, Fan, Field & Stream, Glendale, Silver Streak, Mallard, Nomad, Banner, Davon, Utopia, Vakashunette, Yellowstone, Zipper and DeCamp trailers (as well as many others) as side and top marker lights.
An earlier version of this lens was used on 1950s trailers.
They are mounted with a mounting ring (not included) with no mounting holes. Fresnel optics on top of lens.
This is the lens only. We have not found a source for the metal parts.
Please let us know if your trailer uses these lenses.