Kopp makers mark and lens size marks can be easily read. Beautiful antique amber glass with embedded bubbles.
Vintage KOPP GLASS Railroad Highway Reflector XR7510 - 5-1/4" Blue Hobnail Glass
Vintage KOPP GLASS Railroad Highway Reflector XR7510 - 5-1/4" Red Hobnail Glass
VINTAGE KOPP GLASS RAILROAD LENS 4.75" With Birds And Flower Glass HairlineCrack
Vintage Kopp Glass 4-3/4" Railroad Train Signal-Lantern Lens 1930s Blue
Vintage Kopp Glass 4-3/4" Railroad Train Signal-Lantern Lens 1930s Red