Metal dial. Color of case varies. A few are yellow or red Catalin. The USA made ones I've seen have a luminous metal dial, the Canadian ones have a non-luminous metal dial.
Even though the Canadian ones say "RD 1931" on the back, they were made in the 1940s.
A metal "snap ring" holds the movement in the case.
There are 3 Models of Seth Thomas Seth Thomas "Baby Ben" Catalin Alarm Clock in the database
Red-orange Catalin plastic cased windup alarm clock with Baby Ben movement. Case has flat top with concave corners.
Dates made: Approximate Date: 1940s
Black Catalin plastic cased windup alarm clock with Baby Ben movement. Case has flat top with concave corners.
Dates made: Example Date: December 1946
Black Catalin plastic cased windup alarm clock with Baby Ben movement. Case has flat top with concave corners.
Dates made: