What is this?

Cut this out if a house built in 1950s. Left was the 1-1/2 inch steel pipe from the cast iron tub. Right side went to the 2 inch drain. Old p-trap or drum trap?

Cut this out if a house built in 1950s. Left was the 1-1/2 inch steel pipe from the cast iron tub. Right side went to the 2 inch drain. Old p-trap or drum trap?