The red glass doublet lens on the top left-hand side is embossed "Corning Pat. 12-9-13". It's undoubtedly the oldest of the bunch and is an inner lens to a color light signal. The new old stock larger yellow and red lenses next to it are for crossing gates. They are manufactured out of Lexan and marked "General Signals Inc". I thought the mirrored glass crossing gate backgrounds were neat. They would be located in the back of the flashing light lens housing mechanism to reflect light onto the road. The larger one on the right is unmarked. The middle is very thick glass and has a "WRRS" (Western Railroad Supply Company) marking on it. The unit on the left is marked "Lancaster Glass Corporation Ohio".