American Standard Car Co.

Dick, I did some searching on the web, the American Standard Airslide hopper car was referenced the the GATC airslide 2 bay covered hopper car, these airslide hopper cars were built in the 1950's by General American Transportation Company.

I checked the AtlasO GATC  2 bay airslide hopper cars that I have, O scale with 3-rail trucks, the extension facing the coupler my guess is the part of the pocket for the O scale coupler box or represents the bottom of the center sill bottom cover plate the coupler box butts up against this extension, the lip or extension should go up. I saw one of these kits for sale on the web, the picture shows the parts and accompanying paperwork.