0016, 0046, and 0046K.
Lionel’s OO hopper cars were only offered in full scale versions. The scale sets came with or without the hopper car, while the semi-scale sets never came with a hopper car. This car is entirely die cast. Made only with Southern Pacific lettering.
The three rail 0016 hopper comes in grey or black; the two rail 0046 comes only in black.
Earliest version of 0016 is painted grey with black and white decals.
Similar to the car above this 0016 hopper has the decals inward on the car. This car is actually the same color as the one above.
Last color variation is black with white decals.
Undecaled black 0044 hopper. These unlettered cars were sold through Madison Hardware through the late 1970s. Original unlettered hoppers have unpainted blackened steps. Repainted versions have painted steps.
Here’s a picture of an 0044 in the display box: